The Tor Browser: layout/style/nsStyleStruct.h@deefc01c0e14 (annotated)

layout/style/nsStyleStruct.h@deefc01c0e14 (annotated)

layout/style/nsStyleStruct.h

Thu, 15 Jan 2015 21:03:48 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 21:03:48 +0100
branch: TOR_BUG_9701
changeset 11: deefc01c0e14
permissions: -rw-r--r--

Integrate friendly tips from Tor colleagues to make (or not) 4.5 alpha 3;
This includes removal of overloaded (but unused) methods, and addition of
a overlooked call to DataStruct::SetData(nsISupports, uint32_t, bool.)

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 /*
  * structs that contain the data provided by nsStyleContext, the
  * internal API for computed style data for an element
  */
 #ifndef nsStyleStruct_h___
 #define nsStyleStruct_h___
 #include "mozilla/Attributes.h"
 #include "mozilla/CSSVariableValues.h"
 #include "nsColor.h"
 #include "nsCoord.h"
 #include "nsMargin.h"
 #include "nsRect.h"
 #include "nsFont.h"
 #include "nsStyleCoord.h"
 #include "nsStyleConsts.h"
 #include "nsChangeHint.h"
 #include "nsPresContext.h"
 #include "nsCOMPtr.h"
 #include "nsCOMArray.h"
 #include "nsTArray.h"
 #include "nsIAtom.h"
 #include "nsCSSValue.h"
 #include "imgRequestProxy.h"
 #include "Orientation.h"
 #include <algorithm>
 class nsIFrame;
 class nsIURI;
 class imgIContainer;
 // Includes nsStyleStructID.
 #include "nsStyleStructFwd.h"
 // Bits for each struct.
 // NS_STYLE_INHERIT_BIT defined in nsStyleStructFwd.h
 #define NS_STYLE_INHERIT_MASK              0x000ffffff
 // Additional bits for nsStyleContext's mBits:
 // See nsStyleContext::HasTextDecorationLines
 #define NS_STYLE_HAS_TEXT_DECORATION_LINES 0x001000000
 // See nsStyleContext::HasPseudoElementData.
 #define NS_STYLE_HAS_PSEUDO_ELEMENT_DATA   0x002000000
 // See nsStyleContext::RelevantLinkIsVisited
 #define NS_STYLE_RELEVANT_LINK_VISITED     0x004000000
 // See nsStyleContext::IsStyleIfVisited
 #define NS_STYLE_IS_STYLE_IF_VISITED       0x008000000
 // See nsStyleContext::GetPseudoEnum
 #define NS_STYLE_CONTEXT_TYPE_MASK         0x1f0000000
 #define NS_STYLE_CONTEXT_TYPE_SHIFT        28
 // Additional bits for nsRuleNode's mDependentBits:
 #define NS_RULE_NODE_GC_MARK                0x02000000
 #define NS_RULE_NODE_USED_DIRECTLY          0x04000000
 #define NS_RULE_NODE_IS_IMPORTANT           0x08000000
 #define NS_RULE_NODE_LEVEL_MASK             0xf0000000
 #define NS_RULE_NODE_LEVEL_SHIFT            28
 // The lifetime of these objects is managed by the presshell's arena.
 struct nsStyleFont {
   nsStyleFont(const nsFont& aFont, nsPresContext *aPresContext);
   nsStyleFont(const nsStyleFont& aStyleFont);
   nsStyleFont(nsPresContext *aPresContext);
 private:
   void Init(nsPresContext *aPresContext);
 public:
   ~nsStyleFont(void) {
     MOZ_COUNT_DTOR(nsStyleFont);
   }
   nsChangeHint CalcDifference(const nsStyleFont& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_REFLOW;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   static nsChangeHint CalcFontDifference(const nsFont& aFont1, const nsFont& aFont2);
   static nscoord ZoomText(nsPresContext* aPresContext, nscoord aSize);
   static nscoord UnZoomText(nsPresContext* aPresContext, nscoord aSize);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW;
   void Destroy(nsPresContext* aContext);
   void EnableZoom(nsPresContext* aContext, bool aEnable);
   nsFont  mFont;        // [inherited]
   nscoord mSize;        // [inherited] Our "computed size". Can be different
                         // from mFont.size which is our "actual size" and is
                         // enforced to be >= the user's preferred min-size.
                         // mFont.size should be used for display purposes
                         // while mSize is the value to return in
                         // getComputedStyle() for example.
   uint8_t mGenericID;   // [inherited] generic CSS font family, if any;
                         // value is a kGenericFont_* constant, see nsFont.h.
   // MathML scriptlevel support
   int8_t  mScriptLevel;          // [inherited]
   // MathML  mathvariant support
   uint8_t mMathVariant;          // [inherited]
   // MathML displaystyle support
   uint8_t mMathDisplay;         // [inherited]
   // was mLanguage set based on a lang attribute in the document?
   bool mExplicitLanguage;        // [inherited]
   // should calls to ZoomText() and UnZoomText() be made to the font
   // size on this nsStyleFont?
   bool mAllowZoom;               // [inherited]
   // The value mSize would have had if scriptminsize had never been applied
   nscoord mScriptUnconstrainedSize;
   nscoord mScriptMinSize;        // [inherited] length
   float   mScriptSizeMultiplier; // [inherited]
   nsCOMPtr<nsIAtom> mLanguage;   // [inherited]
 };
 struct nsStyleGradientStop {
   nsStyleCoord mLocation; // percent, coord, calc, none
   nscolor mColor;
 };
 class nsStyleGradient MOZ_FINAL {
 public:
   nsStyleGradient();
   uint8_t mShape;  // NS_STYLE_GRADIENT_SHAPE_*
   uint8_t mSize;   // NS_STYLE_GRADIENT_SIZE_*;
                    // not used (must be FARTHEST_CORNER) for linear shape
   bool mRepeating;
   bool mLegacySyntax;
   nsStyleCoord mBgPosX; // percent, coord, calc, none
   nsStyleCoord mBgPosY; // percent, coord, calc, none
   nsStyleCoord mAngle;  // none, angle
   nsStyleCoord mRadiusX; // percent, coord, calc, none
   nsStyleCoord mRadiusY; // percent, coord, calc, none
   // stops are in the order specified in the stylesheet
   nsTArray<nsStyleGradientStop> mStops;
   bool operator==(const nsStyleGradient& aOther) const;
   bool operator!=(const nsStyleGradient& aOther) const {
     return !(*this == aOther);
   }
   bool IsOpaque();
   bool HasCalc();
   uint32_t Hash(PLDHashNumber aHash);
   NS_INLINE_DECL_REFCOUNTING(nsStyleGradient)
 private:
   // Private destructor, to discourage deletion outside of Release():
   ~nsStyleGradient() {}
   nsStyleGradient(const nsStyleGradient& aOther) MOZ_DELETE;
   nsStyleGradient& operator=(const nsStyleGradient& aOther) MOZ_DELETE;
 };
 enum nsStyleImageType {
   eStyleImageType_Null,
   eStyleImageType_Image,
   eStyleImageType_Gradient,
   eStyleImageType_Element
 };
 /**
  * Represents a paintable image of one of the following types.
  * (1) A real image loaded from an external source.
  * (2) A CSS linear or radial gradient.
  * (3) An element within a document, or an <img>, <video>, or <canvas> element
  *     not in a document.
  * (*) Optionally a crop rect can be set to paint a partial (rectangular)
  * region of an image. (Currently, this feature is only supported with an
  * image of type (1)).
  */
 struct nsStyleImage {
   nsStyleImage();
   ~nsStyleImage();
   nsStyleImage(const nsStyleImage& aOther);
   nsStyleImage& operator=(const nsStyleImage& aOther);
   void SetNull();
   void SetImageData(imgIRequest* aImage);
   void TrackImage(nsPresContext* aContext);
   void UntrackImage(nsPresContext* aContext);
   void SetGradientData(nsStyleGradient* aGradient);
   void SetElementId(const char16_t* aElementId);
   void SetCropRect(nsStyleSides* aCropRect);
   nsStyleImageType GetType() const {
     return mType;
   }
   imgIRequest* GetImageData() const {
     NS_ABORT_IF_FALSE(mType == eStyleImageType_Image, "Data is not an image!");
     NS_ABORT_IF_FALSE(mImageTracked,
                       "Should be tracking any image we're going to use!");
     return mImage;
   }
   nsStyleGradient* GetGradientData() const {
     NS_ASSERTION(mType == eStyleImageType_Gradient, "Data is not a gradient!");
     return mGradient;
   }
   const char16_t* GetElementId() const {
     NS_ASSERTION(mType == eStyleImageType_Element, "Data is not an element!");
     return mElementId;
   }
   nsStyleSides* GetCropRect() const {
     NS_ASSERTION(mType == eStyleImageType_Image,
                  "Only image data can have a crop rect");
     return mCropRect;
   }
   /**
    * Compute the actual crop rect in pixels, using the source image bounds.
    * The computation involves converting percentage unit to pixel unit and
    * clamping each side value to fit in the source image bounds.
    * @param aActualCropRect the computed actual crop rect.
    * @param aIsEntireImage true iff |aActualCropRect| is identical to the
    * source image bounds.
    * @return true iff |aActualCropRect| holds a meaningful value.
    */
   bool ComputeActualCropRect(nsIntRect& aActualCropRect,
                                bool* aIsEntireImage = nullptr) const;
   /**
    * Starts the decoding of a image.
    */
   nsresult StartDecoding() const;
   /**
    * @return true if the item is definitely opaque --- i.e., paints every
    * pixel within its bounds opaquely, and the bounds contains at least a pixel.
    */
   bool IsOpaque() const;
   /**
    * @return true if this image is fully loaded, and its size is calculated;
    * always returns true if |mType| is |eStyleImageType_Gradient| or
    * |eStyleImageType_Element|.
    */
   bool IsComplete() const;
   /**
    * @return true if this image is loaded without error;
    * always returns true if |mType| is |eStyleImageType_Gradient| or
    * |eStyleImageType_Element|.
    */
   bool IsLoaded() const;
   /**
    * @return true if it is 100% confident that this image contains no pixel
    * to draw.
    */
   bool IsEmpty() const {
     // There are some other cases when the image will be empty, for example
     // when the crop rect is empty. However, checking the emptiness of crop
     // rect is non-trivial since each side value can be specified with
     // percentage unit, which can not be evaluated until the source image size
     // is available. Therefore, we currently postpone the evaluation of crop
     // rect until the actual rendering time --- alternatively until GetOpaqueRegion()
     // is called.
     return mType == eStyleImageType_Null;
   }
   bool operator==(const nsStyleImage& aOther) const;
   bool operator!=(const nsStyleImage& aOther) const {
     return !(*this == aOther);
   }
   bool ImageDataEquals(const nsStyleImage& aOther) const
   {
     return GetType() == eStyleImageType_Image &&
            aOther.GetType() == eStyleImageType_Image &&
            GetImageData() == aOther.GetImageData();
   }
   // These methods are used for the caller to caches the sub images created
   // during a border-image paint operation
   inline void SetSubImage(uint8_t aIndex, imgIContainer* aSubImage) const;
   inline imgIContainer* GetSubImage(uint8_t aIndex) const;
 private:
   void DoCopy(const nsStyleImage& aOther);
   // Cache for border-image painting.
   nsCOMArray<imgIContainer> mSubImages;
   nsStyleImageType mType;
   union {
     imgIRequest* mImage;
     nsStyleGradient* mGradient;
     char16_t* mElementId;
   };
   // This is _currently_ used only in conjunction with eStyleImageType_Image.
   nsAutoPtr<nsStyleSides> mCropRect;
 #ifdef DEBUG
   bool mImageTracked;
 #endif
 };
 struct nsStyleColor {
   nsStyleColor(nsPresContext* aPresContext);
   nsStyleColor(const nsStyleColor& aOther);
   ~nsStyleColor(void) {
     MOZ_COUNT_DTOR(nsStyleColor);
   }
   nsChangeHint CalcDifference(const nsStyleColor& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_VISUAL;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics at all.
     return nsChangeHint(0);
   }
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleColor();
     aContext->FreeToShell(sizeof(nsStyleColor), this);
   }
   // Don't add ANY members to this struct!  We can achieve caching in the rule
   // tree (rather than the style tree) by letting color stay by itself! -dwh
   nscolor mColor;                 // [inherited]
 };
 struct nsStyleBackground {
   nsStyleBackground();
   nsStyleBackground(const nsStyleBackground& aOther);
   ~nsStyleBackground();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext);
   nsChangeHint CalcDifference(const nsStyleBackground& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_CombineHint(nsChangeHint_UpdateEffects, NS_STYLE_HINT_VISUAL);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics at all.
     return nsChangeHint(0);
   }
   struct Position;
   friend struct Position;
   struct Position {
     typedef nsStyleCoord::Calc PositionCoord;
     PositionCoord mXPosition, mYPosition;
     // Initialize nothing
     Position() {}
     // Initialize to initial values
     void SetInitialValues();
     // True if the effective background image position described by this depends
     // on the size of the corresponding frame.
     bool DependsOnPositioningAreaSize() const {
       return mXPosition.mPercent != 0.0f || mYPosition.mPercent != 0.0f;
     }
     bool operator==(const Position& aOther) const {
       return mXPosition == aOther.mXPosition &&
              mYPosition == aOther.mYPosition;
     }
     bool operator!=(const Position& aOther) const {
       return !(*this == aOther);
     }
   };
   struct Size;
   friend struct Size;
   struct Size {
     struct Dimension : public nsStyleCoord::Calc {
       nscoord ResolveLengthPercentage(nscoord aAvailable) const {
         double d = double(mPercent) * double(aAvailable) + double(mLength);
         if (d < 0.0)
           return 0;
         return NSToCoordRoundWithClamp(float(d));
       }
     };
     Dimension mWidth, mHeight;
     nscoord ResolveWidthLengthPercentage(const nsSize& aBgPositioningArea) const {
       NS_ABORT_IF_FALSE(mWidthType == eLengthPercentage,
                         "resolving non-length/percent dimension!");
       return mWidth.ResolveLengthPercentage(aBgPositioningArea.width);
     }
     nscoord ResolveHeightLengthPercentage(const nsSize& aBgPositioningArea) const {
       NS_ABORT_IF_FALSE(mHeightType == eLengthPercentage,
                         "resolving non-length/percent dimension!");
       return mHeight.ResolveLengthPercentage(aBgPositioningArea.height);
     }
     // Except for eLengthPercentage, Dimension types which might change
     // how a layer is painted when the corresponding frame's dimensions
     // change *must* precede all dimension types which are agnostic to
     // frame size; see DependsOnDependsOnPositioningAreaSizeSize.
     enum DimensionType {
       // If one of mWidth and mHeight is eContain or eCover, then both are.
       // Also, these two values must equal the corresponding values in
       // kBackgroundSizeKTable.
       eContain, eCover,
       eAuto,
       eLengthPercentage,
       eDimensionType_COUNT
     };
     uint8_t mWidthType, mHeightType;
     // True if the effective image size described by this depends on the size of
     // the corresponding frame, when aImage (which must not have null type) is
     // the background image.
     bool DependsOnPositioningAreaSize(const nsStyleImage& aImage) const;
     // Initialize nothing
     Size() {}
     // Initialize to initial values
     void SetInitialValues();
     bool operator==(const Size& aOther) const;
     bool operator!=(const Size& aOther) const {
       return !(*this == aOther);
     }
   };
   struct Repeat;
   friend struct Repeat;
   struct Repeat {
     uint8_t mXRepeat, mYRepeat;
     // Initialize nothing
     Repeat() {}
     // Initialize to initial values
     void SetInitialValues();
     bool operator==(const Repeat& aOther) const {
       return mXRepeat == aOther.mXRepeat &&
              mYRepeat == aOther.mYRepeat;
     }
     bool operator!=(const Repeat& aOther) const {
       return !(*this == aOther);
     }
   };
   struct Layer;
   friend struct Layer;
   struct Layer {
     uint8_t mAttachment;                // [reset] See nsStyleConsts.h
     uint8_t mClip;                      // [reset] See nsStyleConsts.h
     uint8_t mOrigin;                    // [reset] See nsStyleConsts.h
     uint8_t mBlendMode;                 // [reset] See nsStyleConsts.h
     Repeat mRepeat;                     // [reset] See nsStyleConsts.h
     Position mPosition;                 // [reset]
     nsStyleImage mImage;                // [reset]
     Size mSize;                         // [reset]
     // Initializes only mImage
     Layer();
     ~Layer();
     // Register/unregister images with the document. We do this only
     // after the dust has settled in ComputeBackgroundData.
     void TrackImages(nsPresContext* aContext) {
       if (mImage.GetType() == eStyleImageType_Image)
         mImage.TrackImage(aContext);
     }
     void UntrackImages(nsPresContext* aContext) {
       if (mImage.GetType() == eStyleImageType_Image)
         mImage.UntrackImage(aContext);
     }
     void SetInitialValues();
     // True if the rendering of this layer might change when the size
     // of the background positioning area changes.  This is true for any
     // non-solid-color background whose position or size depends on
     // the size of the positioning area.  It's also true for SVG images
     // whose root <svg> node has a viewBox.
     bool RenderingMightDependOnPositioningAreaSizeChange() const;
     // An equality operator that compares the images using URL-equality
     // rather than pointer-equality.
     bool operator==(const Layer& aOther) const;
     bool operator!=(const Layer& aOther) const {
       return !(*this == aOther);
     }
   };
   // The (positive) number of computed values of each property, since
   // the lengths of the lists are independent.
   uint32_t mAttachmentCount,
            mClipCount,
            mOriginCount,
            mRepeatCount,
            mPositionCount,
            mImageCount,
            mSizeCount,
            mBlendModeCount;
   // Layers are stored in an array, matching the top-to-bottom order in
   // which they are specified in CSS.  The number of layers to be used
   // should come from the background-image property.  We create
   // additional |Layer| objects for *any* property, not just
   // background-image.  This means that the bottommost layer that
   // callers in layout care about (which is also the one whose
   // background-clip applies to the background-color) may not be last
   // layer.  In layers below the bottom layer, properties will be
   // uninitialized unless their count, above, indicates that they are
   // present.
   nsAutoTArray<Layer, 1> mLayers;
   const Layer& BottomLayer() const { return mLayers[mImageCount - 1]; }
   #define NS_FOR_VISIBLE_BACKGROUND_LAYERS_BACK_TO_FRONT(var_, stylebg_) \
     for (uint32_t var_ = (stylebg_) ? (stylebg_)->mImageCount : 1; var_-- != 0; )
   #define NS_FOR_VISIBLE_BACKGROUND_LAYERS_BACK_TO_FRONT_WITH_RANGE(var_, stylebg_, start_, count_) \
     NS_ASSERTION((int32_t)(start_) >= 0 && (uint32_t)(start_) < ((stylebg_) ? (stylebg_)->mImageCount : 1), "Invalid layer start!"); \
     NS_ASSERTION((count_) > 0 && (count_) <= (start_) + 1, "Invalid layer range!"); \
     for (uint32_t var_ = (start_) + 1; var_-- != (uint32_t)((start_) + 1 - (count_)); )
   nscolor mBackgroundColor;       // [reset]
   // FIXME: This (now background-break in css3-background) should
   // probably move into a different struct so that everything in
   // nsStyleBackground is set by the background shorthand.
   uint8_t mBackgroundInlinePolicy; // [reset] See nsStyleConsts.h
   // True if this background is completely transparent.
   bool IsTransparent() const;
   // We have to take slower codepaths for fixed background attachment,
   // but we don't want to do that when there's no image.
   // Not inline because it uses an nsCOMPtr<imgIRequest>
   // FIXME: Should be in nsStyleStructInlines.h.
   bool HasFixedBackground() const;
 };
 // See https://bugzilla.mozilla.org/show_bug.cgi?id=271586#c43 for why
 // this is hard to replace with 'currentColor'.
 #define BORDER_COLOR_FOREGROUND   0x20
 #define OUTLINE_COLOR_INITIAL     0x80
 // FOREGROUND | INITIAL(OUTLINE)
 #define BORDER_COLOR_SPECIAL      0xA0
 #define BORDER_STYLE_MASK         0x1F
 #define NS_SPACING_MARGIN   0
 #define NS_SPACING_PADDING  1
 #define NS_SPACING_BORDER   2
 struct nsStyleMargin {
   nsStyleMargin(void);
   nsStyleMargin(const nsStyleMargin& aMargin);
   ~nsStyleMargin(void) {
     MOZ_COUNT_DTOR(nsStyleMargin);
   }
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW;
   void Destroy(nsPresContext* aContext);
   void RecalcData();
   nsChangeHint CalcDifference(const nsStyleMargin& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_SubtractHint(NS_STYLE_HINT_REFLOW,
                            NS_CombineHint(nsChangeHint_ClearDescendantIntrinsics,
                                           nsChangeHint_NeedDirtyReflow));
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference can return both nsChangeHint_ClearAncestorIntrinsics and
     // nsChangeHint_NeedReflow as inherited hints.
     return nsChangeHint(0);
   }
   nsStyleSides  mMargin;          // [reset] coord, percent, calc, auto
   bool IsWidthDependent() const { return !mHasCachedMargin; }
   bool GetMargin(nsMargin& aMargin) const
   {
     if (mHasCachedMargin) {
       aMargin = mCachedMargin;
       return true;
     }
     return false;
   }
 protected:
   bool          mHasCachedMargin;
   nsMargin      mCachedMargin;
 };
 struct nsStylePadding {
   nsStylePadding(void);
   nsStylePadding(const nsStylePadding& aPadding);
   ~nsStylePadding(void) {
     MOZ_COUNT_DTOR(nsStylePadding);
   }
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW;
   void Destroy(nsPresContext* aContext);
   void RecalcData();
   nsChangeHint CalcDifference(const nsStylePadding& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_SubtractHint(NS_STYLE_HINT_REFLOW,
                            nsChangeHint_ClearDescendantIntrinsics);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference can return nsChangeHint_ClearAncestorIntrinsics as an
     // inherited hint.
     return nsChangeHint(0);
   }
   nsStyleSides  mPadding;         // [reset] coord, percent, calc
   bool IsWidthDependent() const { return !mHasCachedPadding; }
   bool GetPadding(nsMargin& aPadding) const
   {
     if (mHasCachedPadding) {
       aPadding = mCachedPadding;
       return true;
     }
     return false;
   }
 protected:
   bool          mHasCachedPadding;
   nsMargin      mCachedPadding;
 };
 struct nsBorderColors {
   nsBorderColors* mNext;
   nscolor mColor;
   nsBorderColors() : mNext(nullptr), mColor(NS_RGB(0,0,0)) {}
   nsBorderColors(const nscolor& aColor) : mNext(nullptr), mColor(aColor) {}
   ~nsBorderColors();
   nsBorderColors* Clone() const { return Clone(true); }
   static bool Equal(const nsBorderColors* c1,
                       const nsBorderColors* c2) {
     if (c1 == c2)
       return true;
     while (c1 && c2) {
       if (c1->mColor != c2->mColor)
         return false;
       c1 = c1->mNext;
       c2 = c2->mNext;
     }
     // both should be nullptr if these are equal, otherwise one
     // has more colors than another
     return !c1 && !c2;
   }
 private:
   nsBorderColors* Clone(bool aDeep) const;
 };
 struct nsCSSShadowItem {
   nscoord mXOffset;
   nscoord mYOffset;
   nscoord mRadius;
   nscoord mSpread;
   nscolor      mColor;
   bool mHasColor; // Whether mColor should be used
   bool mInset;
   nsCSSShadowItem() : mHasColor(false) {
     MOZ_COUNT_CTOR(nsCSSShadowItem);
   }
   ~nsCSSShadowItem() {
     MOZ_COUNT_DTOR(nsCSSShadowItem);
   }
   bool operator==(const nsCSSShadowItem& aOther) const {
     return (mXOffset == aOther.mXOffset &&
             mYOffset == aOther.mYOffset &&
             mRadius == aOther.mRadius &&
             mHasColor == aOther.mHasColor &&
             mSpread == aOther.mSpread &&
             mInset == aOther.mInset &&
             (!mHasColor || mColor == aOther.mColor));
   }
   bool operator!=(const nsCSSShadowItem& aOther) const {
     return !(*this == aOther);
   }
 };
 class nsCSSShadowArray MOZ_FINAL {
   public:
     void* operator new(size_t aBaseSize, uint32_t aArrayLen) {
       // We can allocate both this nsCSSShadowArray and the
       // actual array in one allocation. The amount of memory to
       // allocate is equal to the class's size + the number of bytes for all
       // but the first array item (because aBaseSize includes one
       // item, see the private declarations)
       return ::operator new(aBaseSize +
                             (aArrayLen - 1) * sizeof(nsCSSShadowItem));
     }
     nsCSSShadowArray(uint32_t aArrayLen) :
       mLength(aArrayLen)
     {
       MOZ_COUNT_CTOR(nsCSSShadowArray);
       for (uint32_t i = 1; i < mLength; ++i) {
         // Make sure we call the constructors of each nsCSSShadowItem
         // (the first one is called for us because we declared it under private)
         new (&mArray[i]) nsCSSShadowItem();
       }
     }
 private:
     // Private destructor, to discourage deletion outside of Release():
     ~nsCSSShadowArray() {
       MOZ_COUNT_DTOR(nsCSSShadowArray);
       for (uint32_t i = 1; i < mLength; ++i) {
         mArray[i].~nsCSSShadowItem();
       }
     }
 public:
     uint32_t Length() const { return mLength; }
     nsCSSShadowItem* ShadowAt(uint32_t i) {
       NS_ABORT_IF_FALSE(i < mLength, "Accessing too high an index in the text shadow array!");
       return &mArray[i];
     }
     const nsCSSShadowItem* ShadowAt(uint32_t i) const {
       NS_ABORT_IF_FALSE(i < mLength, "Accessing too high an index in the text shadow array!");
       return &mArray[i];
     }
     bool HasShadowWithInset(bool aInset) {
       for (uint32_t i = 0; i < mLength; ++i) {
         if (mArray[i].mInset == aInset)
           return true;
       }
       return false;
     }
     bool operator==(const nsCSSShadowArray& aOther) const {
       if (mLength != aOther.Length())
         return false;
       for (uint32_t i = 0; i < mLength; ++i) {
         if (ShadowAt(i) != aOther.ShadowAt(i))
           return false;
       }
       return true;
     }
     NS_INLINE_DECL_REFCOUNTING(nsCSSShadowArray)
   private:
     uint32_t mLength;
     nsCSSShadowItem mArray[1]; // This MUST be the last item
 };
 // Border widths are rounded to the nearest-below integer number of pixels,
 // but values between zero and one device pixels are always rounded up to
 // one device pixel.
 #define NS_ROUND_BORDER_TO_PIXELS(l,tpp) \
   ((l) == 0) ? 0 : std::max((tpp), (l) / (tpp) * (tpp))
 // Outline offset is rounded to the nearest integer number of pixels, but values
 // between zero and one device pixels are always rounded up to one device pixel.
 // Note that the offset can be negative.
 #define NS_ROUND_OFFSET_TO_PIXELS(l,tpp) \
   (((l) == 0) ? 0 : \
     ((l) > 0) ? std::max( (tpp), ((l) + ((tpp) / 2)) / (tpp) * (tpp)) : \
                 std::min(-(tpp), ((l) - ((tpp) / 2)) / (tpp) * (tpp)))
 // Returns if the given border style type is visible or not
 static bool IsVisibleBorderStyle(uint8_t aStyle)
 {
   return (aStyle != NS_STYLE_BORDER_STYLE_NONE &&
           aStyle != NS_STYLE_BORDER_STYLE_HIDDEN);
 }
 struct nsStyleBorder {
   nsStyleBorder(nsPresContext* aContext);
   nsStyleBorder(const nsStyleBorder& aBorder);
   ~nsStyleBorder();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW;
   void Destroy(nsPresContext* aContext);
   nsChangeHint CalcDifference(const nsStyleBorder& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_CombineHint(NS_STYLE_HINT_REFLOW,
                           nsChangeHint_BorderStyleNoneChange);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   void EnsureBorderColors() {
     if (!mBorderColors) {
       mBorderColors = new nsBorderColors*[4];
       if (mBorderColors)
         for (int32_t i = 0; i < 4; i++)
           mBorderColors[i] = nullptr;
     }
   }
   void ClearBorderColors(mozilla::css::Side aSide) {
     if (mBorderColors && mBorderColors[aSide]) {
       delete mBorderColors[aSide];
       mBorderColors[aSide] = nullptr;
     }
   }
   // Return whether aStyle is a visible style.  Invisible styles cause
   // the relevant computed border width to be 0.
   // Note that this does *not* consider the effects of 'border-image':
   // if border-style is none, but there is a loaded border image,
   // HasVisibleStyle will be false even though there *is* a border.
   bool HasVisibleStyle(mozilla::css::Side aSide) const
   {
     return IsVisibleBorderStyle(GetBorderStyle(aSide));
   }
   // aBorderWidth is in twips
   void SetBorderWidth(mozilla::css::Side aSide, nscoord aBorderWidth)
   {
     nscoord roundedWidth =
       NS_ROUND_BORDER_TO_PIXELS(aBorderWidth, mTwipsPerPixel);
     mBorder.Side(aSide) = roundedWidth;
     if (HasVisibleStyle(aSide))
       mComputedBorder.Side(aSide) = roundedWidth;
   }
   // Get the computed border (plus rounding).  This does consider the
   // effects of 'border-style: none', but does not consider
   // 'border-image'.
   const nsMargin& GetComputedBorder() const
   {
     return mComputedBorder;
   }
   bool HasBorder() const
   {
     return mComputedBorder != nsMargin(0,0,0,0) || !mBorderImageSource.IsEmpty();
   }
   // Get the actual border width for a particular side, in appunits.  Note that
   // this is zero if and only if there is no border to be painted for this
   // side.  That is, this value takes into account the border style and the
   // value is rounded to the nearest device pixel by NS_ROUND_BORDER_TO_PIXELS.
   nscoord GetComputedBorderWidth(mozilla::css::Side aSide) const
   {
     return GetComputedBorder().Side(aSide);
   }
   uint8_t GetBorderStyle(mozilla::css::Side aSide) const
   {
     NS_ASSERTION(aSide <= NS_SIDE_LEFT, "bad side");
     return (mBorderStyle[aSide] & BORDER_STYLE_MASK);
   }
   void SetBorderStyle(mozilla::css::Side aSide, uint8_t aStyle)
   {
     NS_ASSERTION(aSide <= NS_SIDE_LEFT, "bad side");
     mBorderStyle[aSide] &= ~BORDER_STYLE_MASK;
     mBorderStyle[aSide] |= (aStyle & BORDER_STYLE_MASK);
     mComputedBorder.Side(aSide) =
       (HasVisibleStyle(aSide) ? mBorder.Side(aSide) : 0);
   }
   inline bool IsBorderImageLoaded() const
   {
     return mBorderImageSource.IsLoaded();
   }
   // Defined in nsStyleStructInlines.h
   inline nsresult RequestDecode();
   void GetBorderColor(mozilla::css::Side aSide, nscolor& aColor,
                       bool& aForeground) const
   {
     aForeground = false;
     NS_ASSERTION(aSide <= NS_SIDE_LEFT, "bad side");
     if ((mBorderStyle[aSide] & BORDER_COLOR_SPECIAL) == 0)
       aColor = mBorderColor[aSide];
     else if (mBorderStyle[aSide] & BORDER_COLOR_FOREGROUND)
       aForeground = true;
     else
       NS_NOTREACHED("OUTLINE_COLOR_INITIAL should not be set here");
   }
   void SetBorderColor(mozilla::css::Side aSide, nscolor aColor)
   {
     NS_ASSERTION(aSide <= NS_SIDE_LEFT, "bad side");
     mBorderColor[aSide] = aColor;
     mBorderStyle[aSide] &= ~BORDER_COLOR_SPECIAL;
   }
   void TrackImage(nsPresContext* aContext)
   {
     if (mBorderImageSource.GetType() == eStyleImageType_Image) {
       mBorderImageSource.TrackImage(aContext);
     }
   }
   void UntrackImage(nsPresContext* aContext)
   {
     if (mBorderImageSource.GetType() == eStyleImageType_Image) {
       mBorderImageSource.UntrackImage(aContext);
     }
   }
   nsMargin GetImageOutset() const;
   void GetCompositeColors(int32_t aIndex, nsBorderColors** aColors) const
   {
     if (!mBorderColors)
       *aColors = nullptr;
     else
       *aColors = mBorderColors[aIndex];
   }
   void AppendBorderColor(int32_t aIndex, nscolor aColor)
   {
     NS_ASSERTION(aIndex >= 0 && aIndex <= 3, "bad side for composite border color");
     nsBorderColors* colorEntry = new nsBorderColors(aColor);
     if (!mBorderColors[aIndex])
       mBorderColors[aIndex] = colorEntry;
     else {
       nsBorderColors* last = mBorderColors[aIndex];
       while (last->mNext)
         last = last->mNext;
       last->mNext = colorEntry;
     }
     mBorderStyle[aIndex] &= ~BORDER_COLOR_SPECIAL;
   }
   void SetBorderToForeground(mozilla::css::Side aSide)
   {
     NS_ASSERTION(aSide <= NS_SIDE_LEFT, "bad side");
     mBorderStyle[aSide] &= ~BORDER_COLOR_SPECIAL;
     mBorderStyle[aSide] |= BORDER_COLOR_FOREGROUND;
   }
   imgIRequest* GetBorderImageRequest() const
   {
     if (mBorderImageSource.GetType() == eStyleImageType_Image) {
       return mBorderImageSource.GetImageData();
     }
     return nullptr;
   }
 public:
   nsBorderColors** mBorderColors;        // [reset] composite (stripe) colors
   nsRefPtr<nsCSSShadowArray> mBoxShadow; // [reset] nullptr for 'none'
 public:
   nsStyleCorners mBorderRadius;       // [reset] coord, percent
   nsStyleImage   mBorderImageSource;  // [reset]
   nsStyleSides   mBorderImageSlice;   // [reset] factor, percent
   nsStyleSides   mBorderImageWidth;   // [reset] length, factor, percent, auto
   nsStyleSides   mBorderImageOutset;  // [reset] length, factor
   uint8_t        mBorderImageFill;    // [reset]
   uint8_t        mBorderImageRepeatH; // [reset] see nsStyleConsts.h
   uint8_t        mBorderImageRepeatV; // [reset]
   uint8_t        mFloatEdge;          // [reset]
 protected:
   // mComputedBorder holds the CSS2.1 computed border-width values.
   // In particular, these widths take into account the border-style
   // for the relevant side, and the values are rounded to the nearest
   // device pixel (which is not part of the definition of computed
   // values). The presence or absence of a border-image does not
   // affect border-width values.
   nsMargin      mComputedBorder;
   // mBorder holds the nscoord values for the border widths as they
   // would be if all the border-style values were visible (not hidden
   // or none).  This member exists so that when we create structs
   // using the copy constructor during style resolution the new
   // structs will know what the specified values of the border were in
   // case they have more specific rules setting the border style.
   //
   // Note that this isn't quite the CSS specified value, since this
   // has had the enumerated border widths converted to lengths, and
   // all lengths converted to twips.  But it's not quite the computed
   // value either. The values are rounded to the nearest device pixel.
   nsMargin      mBorder;
   uint8_t       mBorderStyle[4];  // [reset] See nsStyleConsts.h
   nscolor       mBorderColor[4];  // [reset] the colors to use for a simple
                                   // border.  not used for -moz-border-colors
 private:
   nscoord       mTwipsPerPixel;
   nsStyleBorder& operator=(const nsStyleBorder& aOther) MOZ_DELETE;
 };
 struct nsStyleOutline {
   nsStyleOutline(nsPresContext* aPresContext);
   nsStyleOutline(const nsStyleOutline& aOutline);
   ~nsStyleOutline(void) {
     MOZ_COUNT_DTOR(nsStyleOutline);
   }
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleOutline();
     aContext->FreeToShell(sizeof(nsStyleOutline), this);
   }
   void RecalcData(nsPresContext* aContext);
   nsChangeHint CalcDifference(const nsStyleOutline& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_CombineHint(nsChangeHint_AllReflowHints,
                           nsChangeHint_RepaintFrame);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   nsStyleCorners  mOutlineRadius; // [reset] coord, percent, calc
   // Note that this is a specified value.  You can get the actual values
   // with GetOutlineWidth.  You cannot get the computed value directly.
   nsStyleCoord  mOutlineWidth;    // [reset] coord, enum (see nsStyleConsts.h)
   nscoord       mOutlineOffset;   // [reset]
   bool GetOutlineWidth(nscoord& aWidth) const
   {
     if (mHasCachedOutline) {
       aWidth = mCachedOutlineWidth;
       return true;
     }
     return false;
   }
   uint8_t GetOutlineStyle(void) const
   {
     return (mOutlineStyle & BORDER_STYLE_MASK);
   }
   void SetOutlineStyle(uint8_t aStyle)
   {
     mOutlineStyle &= ~BORDER_STYLE_MASK;
     mOutlineStyle |= (aStyle & BORDER_STYLE_MASK);
   }
   // false means initial value
   bool GetOutlineColor(nscolor& aColor) const
   {
     if ((mOutlineStyle & BORDER_COLOR_SPECIAL) == 0) {
       aColor = mOutlineColor;
       return true;
     }
     return false;
   }
   void SetOutlineColor(nscolor aColor)
   {
     mOutlineColor = aColor;
     mOutlineStyle &= ~BORDER_COLOR_SPECIAL;
   }
   void SetOutlineInitialColor()
   {
     mOutlineStyle |= OUTLINE_COLOR_INITIAL;
   }
   bool GetOutlineInitialColor() const
   {
     return !!(mOutlineStyle & OUTLINE_COLOR_INITIAL);
   }
 protected:
   // This value is the actual value, so it's rounded to the nearest device
   // pixel.
   nscoord       mCachedOutlineWidth;
   nscolor       mOutlineColor;    // [reset]
   bool          mHasCachedOutline;
   uint8_t       mOutlineStyle;    // [reset] See nsStyleConsts.h
   nscoord       mTwipsPerPixel;
 };
 struct nsStyleList {
   nsStyleList(void);
   nsStyleList(const nsStyleList& aStyleList);
   ~nsStyleList(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleList();
     aContext->FreeToShell(sizeof(nsStyleList), this);
   }
   nsChangeHint CalcDifference(const nsStyleList& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   imgRequestProxy* GetListStyleImage() const { return mListStyleImage; }
   void SetListStyleImage(imgRequestProxy* aReq)
   {
     if (mListStyleImage)
       mListStyleImage->UnlockImage();
     mListStyleImage = aReq;
     if (mListStyleImage)
       mListStyleImage->LockImage();
   }
   uint8_t   mListStyleType;             // [inherited] See nsStyleConsts.h
   uint8_t   mListStylePosition;         // [inherited]
 private:
   nsRefPtr<imgRequestProxy> mListStyleImage; // [inherited]
   nsStyleList& operator=(const nsStyleList& aOther) MOZ_DELETE;
 public:
   nsRect        mImageRegion;           // [inherited] the rect to use within an image
 };
 // Computed value of the grid-template-columns or grid-columns-rows property
 // (but *not* grid-template-areas.)
 // http://dev.w3.org/csswg/css-grid/#track-sizing
 //
 // This represents either:
 // * none:
 //   mIsSubgrid is false, all three arrays are empty
 // * <track-list>:
 //   mIsSubgrid is false,
 //   mMinTrackSizingFunctions and mMaxTrackSizingFunctions
 //   are of identical non-zero size,
 //   and mLineNameLists is one element longer than that.
 //   (Delimiting N columns requires N+1 lines:
 //   one before each track, plus one at the very end.)
 //
 //   An omitted <line-names> is still represented in mLineNameLists,
 //   as an empty sub-array.
 //
 //   A <track-size> specified as a single <track-breadth> is represented
 //   as identical min and max sizing functions.
 //
 //   The units for nsStyleCoord are:
 //   * eStyleUnit_Percent represents a <percentage>
 //   * eStyleUnit_FlexFraction represents a <flex> flexible fraction
 //   * eStyleUnit_Coord represents a <length>
 //   * eStyleUnit_Enumerated represents min-content or max-content
 // * subgrid <line-name-list>?:
 //   mIsSubgrid is true,
 //   mLineNameLists may or may not be empty,
 //   mMinTrackSizingFunctions and mMaxTrackSizingFunctions are empty.
 struct nsStyleGridTemplate {
   bool mIsSubgrid;
   nsTArray<nsTArray<nsString>> mLineNameLists;
   nsTArray<nsStyleCoord> mMinTrackSizingFunctions;
   nsTArray<nsStyleCoord> mMaxTrackSizingFunctions;
   nsStyleGridTemplate()
     : mIsSubgrid(false)
   {
   }
   inline bool operator!=(const nsStyleGridTemplate& aOther) const {
     return mLineNameLists != aOther.mLineNameLists ||
            mMinTrackSizingFunctions != aOther.mMinTrackSizingFunctions ||
            mMaxTrackSizingFunctions != aOther.mMaxTrackSizingFunctions;
   }
 };
 struct nsStyleGridLine {
   // http://dev.w3.org/csswg/css-grid/#typedef-grid-line
   bool mHasSpan;
   int32_t mInteger;  // 0 means not provided
   nsString mLineName;  // Empty string means not provided.
   nsStyleGridLine()
     : mHasSpan(false)
     , mInteger(0)
     // mLineName get its default constructor, the empty string
   {
   }
   nsStyleGridLine(const nsStyleGridLine& aOther)
   {
     (*this) = aOther;
   }
   void operator=(const nsStyleGridLine& aOther)
   {
     mHasSpan = aOther.mHasSpan;
     mInteger = aOther.mInteger;
     mLineName = aOther.mLineName;
   }
   bool operator!=(const nsStyleGridLine& aOther) const
   {
     return mHasSpan != aOther.mHasSpan ||
            mInteger != aOther.mInteger ||
            mLineName != aOther.mLineName;
   }
   void SetToInteger(uint32_t value)
   {
     mHasSpan = false;
     mInteger = value;
     mLineName.Truncate();
   }
   void SetAuto()
   {
     mHasSpan = false;
     mInteger = 0;
     mLineName.Truncate();
   }
   bool IsAuto() const
   {
     bool haveInitialValues =  mInteger == 0 && mLineName.IsEmpty();
     MOZ_ASSERT(!(haveInitialValues && mHasSpan),
                "should not have 'span' when other components are "
                "at their initial values");
     return haveInitialValues;
   }
 };
 struct nsStylePosition {
   nsStylePosition(void);
   nsStylePosition(const nsStylePosition& aOther);
   ~nsStylePosition(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStylePosition();
     aContext->FreeToShell(sizeof(nsStylePosition), this);
   }
   nsChangeHint CalcDifference(const nsStylePosition& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_CombineHint(NS_STYLE_HINT_REFLOW,
                           nsChangeHint(nsChangeHint_RecomputePosition |
                                        nsChangeHint_UpdateOverflow));
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference can return both nsChangeHint_ClearAncestorIntrinsics and
     // nsChangeHint_NeedReflow as inherited hints.
     return nsChangeHint(0);
   }
   nsStyleSides  mOffset;                // [reset] coord, percent, calc, auto
   nsStyleCoord  mWidth;                 // [reset] coord, percent, enum, calc, auto
   nsStyleCoord  mMinWidth;              // [reset] coord, percent, enum, calc
   nsStyleCoord  mMaxWidth;              // [reset] coord, percent, enum, calc, none
   nsStyleCoord  mHeight;                // [reset] coord, percent, calc, auto
   nsStyleCoord  mMinHeight;             // [reset] coord, percent, calc
   nsStyleCoord  mMaxHeight;             // [reset] coord, percent, calc, none
   nsStyleCoord  mFlexBasis;             // [reset] coord, percent, enum, calc, auto
   nsStyleCoord  mGridAutoColumnsMin;    // [reset] coord, percent, enum, calc, flex
   nsStyleCoord  mGridAutoColumnsMax;    // [reset] coord, percent, enum, calc, flex
   nsStyleCoord  mGridAutoRowsMin;       // [reset] coord, percent, enum, calc, flex
   nsStyleCoord  mGridAutoRowsMax;       // [reset] coord, percent, enum, calc, flex
   uint8_t       mGridAutoFlow;          // [reset] enumerated. See nsStyleConsts.h
   uint8_t       mBoxSizing;             // [reset] see nsStyleConsts.h
   uint8_t       mAlignContent;          // [reset] see nsStyleConsts.h
   uint8_t       mAlignItems;            // [reset] see nsStyleConsts.h
   uint8_t       mAlignSelf;             // [reset] see nsStyleConsts.h
   uint8_t       mFlexDirection;         // [reset] see nsStyleConsts.h
   uint8_t       mFlexWrap;              // [reset] see nsStyleConsts.h
   uint8_t       mJustifyContent;        // [reset] see nsStyleConsts.h
   int32_t       mOrder;                 // [reset] integer
   float         mFlexGrow;              // [reset] float
   float         mFlexShrink;            // [reset] float
   nsStyleCoord  mZIndex;                // [reset] integer, auto
   // NOTE: Fields so far can be memcpy()'ed, while following fields
   // need to have their copy constructor called when we're being copied.
   // See nsStylePosition::nsStylePosition(const nsStylePosition& aSource)
   // in nsStyleStruct.cpp
   nsStyleGridTemplate mGridTemplateColumns;
   nsStyleGridTemplate mGridTemplateRows;
   // nullptr for 'none'
   nsRefPtr<mozilla::css::GridTemplateAreasValue> mGridTemplateAreas;
   // We represent the "grid-auto-position" property in two parts:
   nsStyleGridLine mGridAutoPositionColumn;
   nsStyleGridLine mGridAutoPositionRow;
   nsStyleGridLine mGridColumnStart;
   nsStyleGridLine mGridColumnEnd;
   nsStyleGridLine mGridRowStart;
   nsStyleGridLine mGridRowEnd;
   bool WidthDependsOnContainer() const
     { return WidthCoordDependsOnContainer(mWidth); }
   bool MinWidthDependsOnContainer() const
     { return WidthCoordDependsOnContainer(mMinWidth); }
   bool MaxWidthDependsOnContainer() const
     { return WidthCoordDependsOnContainer(mMaxWidth); }
   // Note that these functions count 'auto' as depending on the
   // container since that's the case for absolutely positioned elements.
   // However, some callers do not care about this case and should check
   // for it, since it is the most common case.
   // FIXME: We should probably change the assumption to be the other way
   // around.
   bool HeightDependsOnContainer() const
     { return HeightCoordDependsOnContainer(mHeight); }
   bool MinHeightDependsOnContainer() const
     { return HeightCoordDependsOnContainer(mMinHeight); }
   bool MaxHeightDependsOnContainer() const
     { return HeightCoordDependsOnContainer(mMaxHeight); }
   bool OffsetHasPercent(mozilla::css::Side aSide) const
   {
     return mOffset.Get(aSide).HasPercent();
   }
 private:
   static bool WidthCoordDependsOnContainer(const nsStyleCoord &aCoord);
   static bool HeightCoordDependsOnContainer(const nsStyleCoord &aCoord)
   {
     return aCoord.GetUnit() == eStyleUnit_Auto || // CSS 2.1, 10.6.4, item (5)
            aCoord.HasPercent();
   }
 };
 struct nsStyleTextOverflowSide {
   nsStyleTextOverflowSide() : mType(NS_STYLE_TEXT_OVERFLOW_CLIP) {}
   bool operator==(const nsStyleTextOverflowSide& aOther) const {
     return mType == aOther.mType &&
            (mType != NS_STYLE_TEXT_OVERFLOW_STRING ||
             mString == aOther.mString);
   }
   bool operator!=(const nsStyleTextOverflowSide& aOther) const {
     return !(*this == aOther);
   }
   nsString mString;
   uint8_t  mType;
 };
 struct nsStyleTextOverflow {
   nsStyleTextOverflow() : mLogicalDirections(true) {}
   bool operator==(const nsStyleTextOverflow& aOther) const {
     return mLeft == aOther.mLeft && mRight == aOther.mRight;
   }
   bool operator!=(const nsStyleTextOverflow& aOther) const {
     return !(*this == aOther);
   }
   // Returns the value to apply on the left side.
   const nsStyleTextOverflowSide& GetLeft(uint8_t aDirection) const {
     NS_ASSERTION(aDirection == NS_STYLE_DIRECTION_LTR ||
                  aDirection == NS_STYLE_DIRECTION_RTL, "bad direction");
     return !mLogicalDirections || aDirection == NS_STYLE_DIRECTION_LTR ?
              mLeft : mRight;
   }
   // Returns the value to apply on the right side.
   const nsStyleTextOverflowSide& GetRight(uint8_t aDirection) const {
     NS_ASSERTION(aDirection == NS_STYLE_DIRECTION_LTR ||
                  aDirection == NS_STYLE_DIRECTION_RTL, "bad direction");
     return !mLogicalDirections || aDirection == NS_STYLE_DIRECTION_LTR ?
              mRight : mLeft;
   }
   // Returns the first value that was specified.
   const nsStyleTextOverflowSide* GetFirstValue() const {
     return mLogicalDirections ? &mRight : &mLeft;
   }
   // Returns the second value, or null if there was only one value specified.
   const nsStyleTextOverflowSide* GetSecondValue() const {
     return mLogicalDirections ? nullptr : &mRight;
   }
   nsStyleTextOverflowSide mLeft;  // start side when mLogicalDirections is true
   nsStyleTextOverflowSide mRight; // end side when mLogicalDirections is true
   bool mLogicalDirections;  // true when only one value was specified
 };
 struct nsStyleTextReset {
   nsStyleTextReset(void);
   nsStyleTextReset(const nsStyleTextReset& aOther);
   ~nsStyleTextReset(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleTextReset();
     aContext->FreeToShell(sizeof(nsStyleTextReset), this);
   }
   uint8_t GetDecorationStyle() const
   {
     return (mTextDecorationStyle & BORDER_STYLE_MASK);
   }
   void SetDecorationStyle(uint8_t aStyle)
   {
     NS_ABORT_IF_FALSE((aStyle & BORDER_STYLE_MASK) == aStyle,
                       "style doesn't fit");
     mTextDecorationStyle &= ~BORDER_STYLE_MASK;
     mTextDecorationStyle |= (aStyle & BORDER_STYLE_MASK);
   }
   void GetDecorationColor(nscolor& aColor, bool& aForeground) const
   {
     aForeground = false;
     if ((mTextDecorationStyle & BORDER_COLOR_SPECIAL) == 0) {
       aColor = mTextDecorationColor;
     } else if (mTextDecorationStyle & BORDER_COLOR_FOREGROUND) {
       aForeground = true;
     } else {
       NS_NOTREACHED("OUTLINE_COLOR_INITIAL should not be set here");
     }
   }
   void SetDecorationColor(nscolor aColor)
   {
     mTextDecorationColor = aColor;
     mTextDecorationStyle &= ~BORDER_COLOR_SPECIAL;
   }
   void SetDecorationColorToForeground()
   {
     mTextDecorationStyle &= ~BORDER_COLOR_SPECIAL;
     mTextDecorationStyle |= BORDER_COLOR_FOREGROUND;
   }
   nsChangeHint CalcDifference(const nsStyleTextReset& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_REFLOW;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   nsStyleCoord  mVerticalAlign;         // [reset] coord, percent, calc, enum (see nsStyleConsts.h)
   nsStyleTextOverflow mTextOverflow;    // [reset] enum, string
   uint8_t mTextDecorationLine;          // [reset] see nsStyleConsts.h
   uint8_t mUnicodeBidi;                 // [reset] see nsStyleConsts.h
 protected:
   uint8_t mTextDecorationStyle;         // [reset] see nsStyleConsts.h
   nscolor mTextDecorationColor;         // [reset] the colors to use for a decoration lines, not used at currentColor
 };
 struct nsStyleText {
   nsStyleText(void);
   nsStyleText(const nsStyleText& aOther);
   ~nsStyleText(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleText();
     aContext->FreeToShell(sizeof(nsStyleText), this);
   }
   nsChangeHint CalcDifference(const nsStyleText& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   uint8_t mTextAlign;                   // [inherited] see nsStyleConsts.h
   uint8_t mTextAlignLast;               // [inherited] see nsStyleConsts.h
   bool mTextAlignTrue : 1;              // [inherited] see nsStyleConsts.h
   bool mTextAlignLastTrue : 1;          // [inherited] see nsStyleConsts.h
   uint8_t mTextTransform;               // [inherited] see nsStyleConsts.h
   uint8_t mWhiteSpace;                  // [inherited] see nsStyleConsts.h
   uint8_t mWordBreak;                   // [inherited] see nsStyleConsts.h
   uint8_t mWordWrap;                    // [inherited] see nsStyleConsts.h
   uint8_t mHyphens;                     // [inherited] see nsStyleConsts.h
   uint8_t mTextSizeAdjust;              // [inherited] see nsStyleConsts.h
   uint8_t mTextOrientation;             // [inherited] see nsStyleConsts.h
   uint8_t mTextCombineUpright;          // [inherited] see nsStyleConsts.h
   uint8_t mControlCharacterVisibility;  // [inherited] see nsStyleConsts.h
   int32_t mTabSize;                     // [inherited] see nsStyleConsts.h
   nscoord mWordSpacing;                 // [inherited]
   nsStyleCoord  mLetterSpacing;         // [inherited] coord, normal
   nsStyleCoord  mLineHeight;            // [inherited] coord, factor, normal
   nsStyleCoord  mTextIndent;            // [inherited] coord, percent, calc
   nsRefPtr<nsCSSShadowArray> mTextShadow; // [inherited] nullptr in case of a zero-length
   bool WhiteSpaceIsSignificant() const {
     return mWhiteSpace == NS_STYLE_WHITESPACE_PRE ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_WRAP ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_DISCARD_NEWLINES;
   }
   bool NewlineIsSignificant() const {
     return mWhiteSpace == NS_STYLE_WHITESPACE_PRE ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_WRAP ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_LINE;
   }
   bool NewlineIsDiscarded() const {
     return mWhiteSpace == NS_STYLE_WHITESPACE_PRE_DISCARD_NEWLINES;
   }
   bool WhiteSpaceOrNewlineIsSignificant() const {
     return mWhiteSpace == NS_STYLE_WHITESPACE_PRE ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_WRAP ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_LINE ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_DISCARD_NEWLINES;
   }
   bool WhiteSpaceCanWrapStyle() const {
     return mWhiteSpace == NS_STYLE_WHITESPACE_NORMAL ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_WRAP ||
            mWhiteSpace == NS_STYLE_WHITESPACE_PRE_LINE;
   }
   bool WordCanWrapStyle() const {
     return WhiteSpaceCanWrapStyle() &&
            mWordWrap == NS_STYLE_WORDWRAP_BREAK_WORD;
   }
   // These are defined in nsStyleStructInlines.h.
   inline bool HasTextShadow() const;
   inline nsCSSShadowArray* GetTextShadow() const;
   // The aContextFrame argument on each of these is the frame this
   // style struct is for.  If the frame is for SVG text, the return
   // value will be massaged to be something that makes sense for
   // SVG text.
   inline bool WhiteSpaceCanWrap(const nsIFrame* aContextFrame) const;
   inline bool WordCanWrap(const nsIFrame* aContextFrame) const;
 };
 struct nsStyleImageOrientation {
   static nsStyleImageOrientation CreateAsAngleAndFlip(double aRadians,
                                                       bool aFlip) {
     uint8_t orientation(0);
     // Compute the final angle value, rounding to the closest quarter turn.
     double roundedAngle = fmod(aRadians, 2 * M_PI);
     if      (roundedAngle < 0.25 * M_PI) orientation = ANGLE_0;
     else if (roundedAngle < 0.75 * M_PI) orientation = ANGLE_90;
     else if (roundedAngle < 1.25 * M_PI) orientation = ANGLE_180;
     else if (roundedAngle < 1.75 * M_PI) orientation = ANGLE_270;
     else                                 orientation = ANGLE_0;
     // Add a bit for 'flip' if needed.
     if (aFlip)
       orientation |= FLIP_MASK;
     return nsStyleImageOrientation(orientation);
   }
   static nsStyleImageOrientation CreateAsFlip() {
     return nsStyleImageOrientation(FLIP_MASK);
   }
   static nsStyleImageOrientation CreateAsFromImage() {
     return nsStyleImageOrientation(FROM_IMAGE_MASK);
   }
   // The default constructor yields 0 degrees of rotation and no flip.
   nsStyleImageOrientation() : mOrientation(0) { }
   bool IsDefault()   const { return mOrientation == 0; }
   bool IsFlipped()   const { return mOrientation & FLIP_MASK; }
   bool IsFromImage() const { return mOrientation & FROM_IMAGE_MASK; }
   mozilla::image::Angle Angle() const {
     switch (mOrientation & ORIENTATION_MASK) {
       case ANGLE_0:   return mozilla::image::Angle::D0;
       case ANGLE_90:  return mozilla::image::Angle::D90;
       case ANGLE_180: return mozilla::image::Angle::D180;
       case ANGLE_270: return mozilla::image::Angle::D270;
       default:
         NS_NOTREACHED("Unexpected angle");
         return mozilla::image::Angle::D0;
     }
   }
   nsStyleCoord AngleAsCoord() const {
     switch (mOrientation & ORIENTATION_MASK) {
       case ANGLE_0:   return nsStyleCoord(0.0f,   eStyleUnit_Degree);
       case ANGLE_90:  return nsStyleCoord(90.0f,  eStyleUnit_Degree);
       case ANGLE_180: return nsStyleCoord(180.0f, eStyleUnit_Degree);
       case ANGLE_270: return nsStyleCoord(270.0f, eStyleUnit_Degree);
       default:
         NS_NOTREACHED("Unexpected angle");
         return nsStyleCoord();
     }
   }
   bool operator==(const nsStyleImageOrientation& aOther) const {
     return aOther.mOrientation == mOrientation;
   }
   bool operator!=(const nsStyleImageOrientation& aOther) const {
     return !(*this == aOther);
   }
 protected:
   enum Bits {
     ORIENTATION_MASK = 0x1 | 0x2,  // The bottom two bits are the angle.
     FLIP_MASK        = 0x4,        // Whether the image should be flipped.
     FROM_IMAGE_MASK  = 0x8,        // Whether the image's inherent orientation
   };                               // should be used.
   enum Angles {
     ANGLE_0   = 0,
     ANGLE_90  = 1,
     ANGLE_180 = 2,
     ANGLE_270 = 3,
   };
   explicit nsStyleImageOrientation(uint8_t aOrientation)
     : mOrientation(aOrientation)
   { }
   uint8_t mOrientation;
 };
 struct nsStyleVisibility {
   nsStyleVisibility(nsPresContext* aPresContext);
   nsStyleVisibility(const nsStyleVisibility& aVisibility);
   ~nsStyleVisibility() {
     MOZ_COUNT_DTOR(nsStyleVisibility);
   }
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleVisibility();
     aContext->FreeToShell(sizeof(nsStyleVisibility), this);
   }
   nsChangeHint CalcDifference(const nsStyleVisibility& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   nsStyleImageOrientation mImageOrientation;  // [inherited]
   uint8_t mDirection;                  // [inherited] see nsStyleConsts.h NS_STYLE_DIRECTION_*
   uint8_t mVisible;                    // [inherited]
   uint8_t mPointerEvents;              // [inherited] see nsStyleConsts.h
   uint8_t mWritingMode;                // [inherited] see nsStyleConsts.h
   bool IsVisible() const {
     return (mVisible == NS_STYLE_VISIBILITY_VISIBLE);
   }
   bool IsVisibleOrCollapsed() const {
     return ((mVisible == NS_STYLE_VISIBILITY_VISIBLE) ||
             (mVisible == NS_STYLE_VISIBILITY_COLLAPSE));
   }
   inline uint8_t GetEffectivePointerEvents(nsIFrame* aFrame) const;
 };
 struct nsTimingFunction {
   enum Type { Function, StepStart, StepEnd };
   explicit nsTimingFunction(int32_t aTimingFunctionType
                               = NS_STYLE_TRANSITION_TIMING_FUNCTION_EASE)
   {
     AssignFromKeyword(aTimingFunctionType);
   }
   nsTimingFunction(float x1, float y1, float x2, float y2)
     : mType(Function)
   {
     mFunc.mX1 = x1;
     mFunc.mY1 = y1;
     mFunc.mX2 = x2;
     mFunc.mY2 = y2;
   }
   nsTimingFunction(Type aType, uint32_t aSteps)
     : mType(aType)
   {
     NS_ABORT_IF_FALSE(mType == StepStart || mType == StepEnd, "wrong type");
     mSteps = aSteps;
   }
   nsTimingFunction(const nsTimingFunction& aOther)
   {
     *this = aOther;
   }
   Type mType;
   union {
     struct {
       float mX1;
       float mY1;
       float mX2;
       float mY2;
     } mFunc;
     uint32_t mSteps;
   };
   nsTimingFunction&
   operator=(const nsTimingFunction& aOther)
   {
     if (&aOther == this)
       return *this;
     mType = aOther.mType;
     if (mType == Function) {
       mFunc.mX1 = aOther.mFunc.mX1;
       mFunc.mY1 = aOther.mFunc.mY1;
       mFunc.mX2 = aOther.mFunc.mX2;
       mFunc.mY2 = aOther.mFunc.mY2;
     } else {
       mSteps = aOther.mSteps;
     }
     return *this;
   }
   bool operator==(const nsTimingFunction& aOther) const
   {
     if (mType != aOther.mType) {
       return false;
     }
     if (mType == Function) {
       return mFunc.mX1 == aOther.mFunc.mX1 && mFunc.mY1 == aOther.mFunc.mY1 &&
              mFunc.mX2 == aOther.mFunc.mX2 && mFunc.mY2 == aOther.mFunc.mY2;
     }
     return mSteps == aOther.mSteps;
   }
   bool operator!=(const nsTimingFunction& aOther) const
   {
     return !(*this == aOther);
   }
 private:
   void AssignFromKeyword(int32_t aTimingFunctionType);
 };
 struct nsTransition {
   nsTransition() { /* leaves uninitialized; see also SetInitialValues */ }
   explicit nsTransition(const nsTransition& aCopy);
   void SetInitialValues();
   // Delay and Duration are in milliseconds
   const nsTimingFunction& GetTimingFunction() const { return mTimingFunction; }
   float GetDelay() const { return mDelay; }
   float GetDuration() const { return mDuration; }
   nsCSSProperty GetProperty() const { return mProperty; }
   nsIAtom* GetUnknownProperty() const { return mUnknownProperty; }
   void SetTimingFunction(const nsTimingFunction& aTimingFunction)
     { mTimingFunction = aTimingFunction; }
   void SetDelay(float aDelay) { mDelay = aDelay; }
   void SetDuration(float aDuration) { mDuration = aDuration; }
   void SetProperty(nsCSSProperty aProperty)
     {
       NS_ASSERTION(aProperty != eCSSProperty_UNKNOWN, "invalid property");
       mProperty = aProperty;
     }
   void SetUnknownProperty(const nsAString& aUnknownProperty);
   void CopyPropertyFrom(const nsTransition& aOther)
     {
       mProperty = aOther.mProperty;
       mUnknownProperty = aOther.mUnknownProperty;
     }
   nsTimingFunction& TimingFunctionSlot() { return mTimingFunction; }
 private:
   nsTimingFunction mTimingFunction;
   float mDuration;
   float mDelay;
   nsCSSProperty mProperty;
   nsCOMPtr<nsIAtom> mUnknownProperty; // used when mProperty is
                                       // eCSSProperty_UNKNOWN
 };
 struct nsAnimation {
   nsAnimation() { /* leaves uninitialized; see also SetInitialValues */ }
   explicit nsAnimation(const nsAnimation& aCopy);
   void SetInitialValues();
   // Delay and Duration are in milliseconds
   const nsTimingFunction& GetTimingFunction() const { return mTimingFunction; }
   float GetDelay() const { return mDelay; }
   float GetDuration() const { return mDuration; }
   const nsString& GetName() const { return mName; }
   uint8_t GetDirection() const { return mDirection; }
   uint8_t GetFillMode() const { return mFillMode; }
   uint8_t GetPlayState() const { return mPlayState; }
   float GetIterationCount() const { return mIterationCount; }
   void SetTimingFunction(const nsTimingFunction& aTimingFunction)
     { mTimingFunction = aTimingFunction; }
   void SetDelay(float aDelay) { mDelay = aDelay; }
   void SetDuration(float aDuration) { mDuration = aDuration; }
   void SetName(const nsSubstring& aName) { mName = aName; }
   void SetDirection(uint8_t aDirection) { mDirection = aDirection; }
   void SetFillMode(uint8_t aFillMode) { mFillMode = aFillMode; }
   void SetPlayState(uint8_t aPlayState) { mPlayState = aPlayState; }
   void SetIterationCount(float aIterationCount)
     { mIterationCount = aIterationCount; }
   nsTimingFunction& TimingFunctionSlot() { return mTimingFunction; }
 private:
   nsTimingFunction mTimingFunction;
   float mDuration;
   float mDelay;
   nsString mName; // empty string for 'none'
   uint8_t mDirection;
   uint8_t mFillMode;
   uint8_t mPlayState;
   float mIterationCount; // NS_IEEEPositiveInfinity() means infinite
 };
 struct nsStyleDisplay {
   nsStyleDisplay();
   nsStyleDisplay(const nsStyleDisplay& aOther);
   ~nsStyleDisplay() {
     MOZ_COUNT_DTOR(nsStyleDisplay);
   }
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleDisplay();
     aContext->FreeToShell(sizeof(nsStyleDisplay), this);
   }
   nsChangeHint CalcDifference(const nsStyleDisplay& aOther) const;
   static nsChangeHint MaxDifference() {
     // All the parts of FRAMECHANGE are present in CalcDifference.
     return nsChangeHint(NS_STYLE_HINT_FRAMECHANGE |
                         nsChangeHint_UpdateOpacityLayer |
                         nsChangeHint_UpdateTransformLayer |
                         nsChangeHint_UpdateOverflow |
                         nsChangeHint_UpdatePostTransformOverflow |
                         nsChangeHint_AddOrRemoveTransform);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference can return both nsChangeHint_ClearAncestorIntrinsics and
     // nsChangeHint_NeedReflow as inherited hints.
     return nsChangeHint(0);
   }
   // We guarantee that if mBinding is non-null, so are mBinding->GetURI() and
   // mBinding->mOriginPrincipal.
   nsRefPtr<mozilla::css::URLValue> mBinding;    // [reset]
   nsRect  mClip;                // [reset] offsets from upper-left border edge
   float   mOpacity;             // [reset]
   uint8_t mDisplay;             // [reset] see nsStyleConsts.h NS_STYLE_DISPLAY_*
   uint8_t mOriginalDisplay;     // [reset] saved mDisplay for position:absolute/fixed
                                 //         and float:left/right; otherwise equal
                                 //         to mDisplay
   uint8_t mAppearance;          // [reset]
   uint8_t mPosition;            // [reset] see nsStyleConsts.h
   uint8_t mFloats;              // [reset] see nsStyleConsts.h NS_STYLE_FLOAT_*
   uint8_t mOriginalFloats;      // [reset] saved mFloats for position:absolute/fixed;
                                 //         otherwise equal to mFloats
   uint8_t mBreakType;           // [reset] see nsStyleConsts.h NS_STYLE_CLEAR_*
   uint8_t mBreakInside;         // [reset] NS_STYLE_PAGE_BREAK_AUTO/AVOID
   bool mBreakBefore;    // [reset]
   bool mBreakAfter;     // [reset]
   uint8_t mOverflowX;           // [reset] see nsStyleConsts.h
   uint8_t mOverflowY;           // [reset] see nsStyleConsts.h
   uint8_t mOverflowClipBox;     // [reset] see nsStyleConsts.h
   uint8_t mResize;              // [reset] see nsStyleConsts.h
   uint8_t mClipFlags;           // [reset] see nsStyleConsts.h
   uint8_t mOrient;              // [reset] see nsStyleConsts.h
   uint8_t mMixBlendMode;        // [reset] see nsStyleConsts.h
   uint8_t mWillChangeBitField;  // [reset] see nsStyleConsts.h. Stores a
                                 // bitfield representation of the properties
                                 // that are frequently queried. This should
                                 // match mWillChange. Also tracks if any of the
                                 // properties in the will-change list require
                                 // a stacking context.
   nsAutoTArray<nsString, 1> mWillChange;
   uint8_t mTouchAction;         // [reset] see nsStyleConsts.h
   // mSpecifiedTransform is the list of transform functions as
   // specified, or null to indicate there is no transform.  (inherit or
   // initial are replaced by an actual list of transform functions, or
   // null, as appropriate.)
   uint8_t mBackfaceVisibility;
   uint8_t mTransformStyle;
   nsRefPtr<nsCSSValueSharedList> mSpecifiedTransform; // [reset]
   nsStyleCoord mTransformOrigin[3]; // [reset] percent, coord, calc, 3rd param is coord, calc only
   nsStyleCoord mChildPerspective; // [reset] coord
   nsStyleCoord mPerspectiveOrigin[2]; // [reset] percent, coord, calc
   nsAutoTArray<nsTransition, 1> mTransitions; // [reset]
   // The number of elements in mTransitions that are not from repeating
   // a list due to another property being longer.
   uint32_t mTransitionTimingFunctionCount,
            mTransitionDurationCount,
            mTransitionDelayCount,
            mTransitionPropertyCount;
   nsAutoTArray<nsAnimation, 1> mAnimations; // [reset]
   // The number of elements in mAnimations that are not from repeating
   // a list due to another property being longer.
   uint32_t mAnimationTimingFunctionCount,
            mAnimationDurationCount,
            mAnimationDelayCount,
            mAnimationNameCount,
            mAnimationDirectionCount,
            mAnimationFillModeCount,
            mAnimationPlayStateCount,
            mAnimationIterationCountCount;
   bool IsBlockInsideStyle() const {
     return NS_STYLE_DISPLAY_BLOCK == mDisplay ||
            NS_STYLE_DISPLAY_LIST_ITEM == mDisplay ||
            NS_STYLE_DISPLAY_INLINE_BLOCK == mDisplay;
     // Should TABLE_CELL and TABLE_CAPTION go here?  They have
     // block frames nested inside of them.
     // (But please audit all callers before changing.)
   }
   bool IsBlockOutsideStyle() const {
     return NS_STYLE_DISPLAY_BLOCK == mDisplay ||
            NS_STYLE_DISPLAY_FLEX == mDisplay ||
            NS_STYLE_DISPLAY_GRID == mDisplay ||
            NS_STYLE_DISPLAY_LIST_ITEM == mDisplay ||
            NS_STYLE_DISPLAY_TABLE == mDisplay;
   }
   static bool IsDisplayTypeInlineOutside(uint8_t aDisplay) {
     return NS_STYLE_DISPLAY_INLINE == aDisplay ||
            NS_STYLE_DISPLAY_INLINE_BLOCK == aDisplay ||
            NS_STYLE_DISPLAY_INLINE_TABLE == aDisplay ||
            NS_STYLE_DISPLAY_INLINE_BOX == aDisplay ||
            NS_STYLE_DISPLAY_INLINE_FLEX == aDisplay ||
            NS_STYLE_DISPLAY_INLINE_GRID == aDisplay ||
            NS_STYLE_DISPLAY_INLINE_XUL_GRID == aDisplay ||
            NS_STYLE_DISPLAY_INLINE_STACK == aDisplay;
   }
   bool IsInlineOutsideStyle() const {
     return IsDisplayTypeInlineOutside(mDisplay);
   }
   bool IsOriginalDisplayInlineOutsideStyle() const {
     return IsDisplayTypeInlineOutside(mOriginalDisplay);
   }
   bool IsInnerTableStyle() const {
     return NS_STYLE_DISPLAY_TABLE_CAPTION == mDisplay ||
            NS_STYLE_DISPLAY_TABLE_CELL == mDisplay ||
            NS_STYLE_DISPLAY_TABLE_ROW == mDisplay ||
            NS_STYLE_DISPLAY_TABLE_ROW_GROUP == mDisplay ||
            NS_STYLE_DISPLAY_TABLE_HEADER_GROUP == mDisplay ||
            NS_STYLE_DISPLAY_TABLE_FOOTER_GROUP == mDisplay ||
            NS_STYLE_DISPLAY_TABLE_COLUMN == mDisplay ||
            NS_STYLE_DISPLAY_TABLE_COLUMN_GROUP == mDisplay;
   }
   bool IsFloatingStyle() const {
     return NS_STYLE_FLOAT_NONE != mFloats;
   }
   bool IsAbsolutelyPositionedStyle() const {
     return NS_STYLE_POSITION_ABSOLUTE == mPosition ||
            NS_STYLE_POSITION_FIXED == mPosition;
   }
   bool IsRelativelyPositionedStyle() const {
     return NS_STYLE_POSITION_RELATIVE == mPosition ||
            NS_STYLE_POSITION_STICKY == mPosition;
   }
   bool IsScrollableOverflow() const {
     // mOverflowX and mOverflowY always match when one of them is
     // NS_STYLE_OVERFLOW_VISIBLE or NS_STYLE_OVERFLOW_CLIP.
     return mOverflowX != NS_STYLE_OVERFLOW_VISIBLE &&
            mOverflowX != NS_STYLE_OVERFLOW_CLIP;
   }
   /* Returns whether the element has the -moz-transform property
    * or a related property. */
   bool HasTransformStyle() const {
     return mSpecifiedTransform != nullptr ||
            mTransformStyle == NS_STYLE_TRANSFORM_STYLE_PRESERVE_3D ||
            (mWillChangeBitField & NS_STYLE_WILL_CHANGE_TRANSFORM);
   }
   bool HasPerspectiveStyle() const {
     return mChildPerspective.GetUnit() == eStyleUnit_Coord;
   }
   bool BackfaceIsHidden() const {
     return mBackfaceVisibility == NS_STYLE_BACKFACE_VISIBILITY_HIDDEN;
   }
   // These are defined in nsStyleStructInlines.h.
   // The aContextFrame argument on each of these is the frame this
   // style struct is for.  If the frame is for SVG text, the return
   // value will be massaged to be something that makes sense for
   // SVG text.
   inline bool IsBlockInside(const nsIFrame* aContextFrame) const;
   inline bool IsBlockOutside(const nsIFrame* aContextFrame) const;
   inline bool IsInlineOutside(const nsIFrame* aContextFrame) const;
   inline bool IsOriginalDisplayInlineOutside(const nsIFrame* aContextFrame) const;
   inline uint8_t GetDisplay(const nsIFrame* aContextFrame) const;
   inline bool IsFloating(const nsIFrame* aContextFrame) const;
   inline bool IsPositioned(const nsIFrame* aContextFrame) const;
   inline bool IsRelativelyPositioned(const nsIFrame* aContextFrame) const;
   inline bool IsAbsolutelyPositioned(const nsIFrame* aContextFrame) const;
   /* Returns whether the element has the -moz-transform property
    * or a related property, and supports CSS transforms. */
   inline bool HasTransform(const nsIFrame* aContextFrame) const;
 };
 struct nsStyleTable {
   nsStyleTable(void);
   nsStyleTable(const nsStyleTable& aOther);
   ~nsStyleTable(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleTable();
     aContext->FreeToShell(sizeof(nsStyleTable), this);
   }
   nsChangeHint CalcDifference(const nsStyleTable& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   uint8_t       mLayoutStrategy;// [reset] see nsStyleConsts.h NS_STYLE_TABLE_LAYOUT_*
   uint8_t       mFrame;         // [reset] see nsStyleConsts.h NS_STYLE_TABLE_FRAME_*
   uint8_t       mRules;         // [reset] see nsStyleConsts.h NS_STYLE_TABLE_RULES_*
   int32_t       mSpan;          // [reset] the number of columns spanned by a colgroup or col
 };
 struct nsStyleTableBorder {
   nsStyleTableBorder(nsPresContext* aContext);
   nsStyleTableBorder(const nsStyleTableBorder& aOther);
   ~nsStyleTableBorder(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleTableBorder();
     aContext->FreeToShell(sizeof(nsStyleTableBorder), this);
   }
   nsChangeHint CalcDifference(const nsStyleTableBorder& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   nscoord       mBorderSpacingX;// [inherited]
   nscoord       mBorderSpacingY;// [inherited]
   uint8_t       mBorderCollapse;// [inherited]
   uint8_t       mCaptionSide;   // [inherited]
   uint8_t       mEmptyCells;    // [inherited]
 };
 enum nsStyleContentType {
   eStyleContentType_String        = 1,
   eStyleContentType_Image         = 10,
   eStyleContentType_Attr          = 20,
   eStyleContentType_Counter       = 30,
   eStyleContentType_Counters      = 31,
   eStyleContentType_OpenQuote     = 40,
   eStyleContentType_CloseQuote    = 41,
   eStyleContentType_NoOpenQuote   = 42,
   eStyleContentType_NoCloseQuote  = 43,
   eStyleContentType_AltContent    = 50,
   eStyleContentType_Uninitialized
 };
 struct nsStyleContentData {
   nsStyleContentType  mType;
   union {
     char16_t *mString;
     imgRequestProxy *mImage;
     nsCSSValue::Array* mCounters;
   } mContent;
 #ifdef DEBUG
   bool mImageTracked;
 #endif
   nsStyleContentData()
     : mType(eStyleContentType_Uninitialized)
 #ifdef DEBUG
     , mImageTracked(false)
 #endif
   { mContent.mString = nullptr; }
   ~nsStyleContentData();
   nsStyleContentData& operator=(const nsStyleContentData& aOther);
   bool operator==(const nsStyleContentData& aOther) const;
   bool operator!=(const nsStyleContentData& aOther) const {
     return !(*this == aOther);
   }
   void TrackImage(nsPresContext* aContext);
   void UntrackImage(nsPresContext* aContext);
   void SetImage(imgRequestProxy* aRequest)
   {
     NS_ABORT_IF_FALSE(!mImageTracked,
                       "Setting a new image without untracking the old one!");
     NS_ABORT_IF_FALSE(mType == eStyleContentType_Image, "Wrong type!");
     NS_IF_ADDREF(mContent.mImage = aRequest);
   }
 private:
   nsStyleContentData(const nsStyleContentData&); // not to be implemented
 };
 struct nsStyleCounterData {
   nsString  mCounter;
   int32_t   mValue;
 };
 #define DELETE_ARRAY_IF(array)  if (array) { delete[] array; array = nullptr; }
 struct nsStyleQuotes {
   nsStyleQuotes();
   nsStyleQuotes(const nsStyleQuotes& aQuotes);
   ~nsStyleQuotes();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleQuotes();
     aContext->FreeToShell(sizeof(nsStyleQuotes), this);
   }
   void SetInitial();
   void CopyFrom(const nsStyleQuotes& aSource);
   nsChangeHint CalcDifference(const nsStyleQuotes& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   uint32_t  QuotesCount(void) const { return mQuotesCount; } // [inherited]
   const nsString* OpenQuoteAt(uint32_t aIndex) const
   {
     NS_ASSERTION(aIndex < mQuotesCount, "out of range");
     return mQuotes + (aIndex * 2);
   }
   const nsString* CloseQuoteAt(uint32_t aIndex) const
   {
     NS_ASSERTION(aIndex < mQuotesCount, "out of range");
     return mQuotes + (aIndex * 2 + 1);
   }
   nsresult  GetQuotesAt(uint32_t aIndex, nsString& aOpen, nsString& aClose) const {
     if (aIndex < mQuotesCount) {
       aIndex *= 2;
       aOpen = mQuotes[aIndex];
       aClose = mQuotes[++aIndex];
       return NS_OK;
     }
     return NS_ERROR_ILLEGAL_VALUE;
   }
   nsresult  AllocateQuotes(uint32_t aCount) {
     if (aCount != mQuotesCount) {
       DELETE_ARRAY_IF(mQuotes);
       if (aCount) {
         mQuotes = new nsString[aCount * 2];
         if (! mQuotes) {
           mQuotesCount = 0;
           return NS_ERROR_OUT_OF_MEMORY;
         }
       }
       mQuotesCount = aCount;
     }
     return NS_OK;
   }
   nsresult  SetQuotesAt(uint32_t aIndex, const nsString& aOpen, const nsString& aClose) {
     if (aIndex < mQuotesCount) {
       aIndex *= 2;
       mQuotes[aIndex] = aOpen;
       mQuotes[++aIndex] = aClose;
       return NS_OK;
     }
     return NS_ERROR_ILLEGAL_VALUE;
   }
 protected:
   uint32_t            mQuotesCount;
   nsString*           mQuotes;
 };
 struct nsStyleContent {
   nsStyleContent(void);
   nsStyleContent(const nsStyleContent& aContent);
   ~nsStyleContent(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext);
   nsChangeHint CalcDifference(const nsStyleContent& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   uint32_t  ContentCount(void) const  { return mContentCount; } // [reset]
   const nsStyleContentData& ContentAt(uint32_t aIndex) const {
     NS_ASSERTION(aIndex < mContentCount, "out of range");
     return mContents[aIndex];
   }
   nsStyleContentData& ContentAt(uint32_t aIndex) {
     NS_ASSERTION(aIndex < mContentCount, "out of range");
     return mContents[aIndex];
   }
   nsresult AllocateContents(uint32_t aCount);
   uint32_t  CounterIncrementCount(void) const { return mIncrementCount; }  // [reset]
   const nsStyleCounterData* GetCounterIncrementAt(uint32_t aIndex) const {
     NS_ASSERTION(aIndex < mIncrementCount, "out of range");
     return &mIncrements[aIndex];
   }
   nsresult  AllocateCounterIncrements(uint32_t aCount) {
     if (aCount != mIncrementCount) {
       DELETE_ARRAY_IF(mIncrements);
       if (aCount) {
         mIncrements = new nsStyleCounterData[aCount];
         if (! mIncrements) {
           mIncrementCount = 0;
           return NS_ERROR_OUT_OF_MEMORY;
         }
       }
       mIncrementCount = aCount;
     }
     return NS_OK;
   }
   nsresult  SetCounterIncrementAt(uint32_t aIndex, const nsString& aCounter, int32_t aIncrement) {
     if (aIndex < mIncrementCount) {
       mIncrements[aIndex].mCounter = aCounter;
       mIncrements[aIndex].mValue = aIncrement;
       return NS_OK;
     }
     return NS_ERROR_ILLEGAL_VALUE;
   }
   uint32_t  CounterResetCount(void) const { return mResetCount; }  // [reset]
   const nsStyleCounterData* GetCounterResetAt(uint32_t aIndex) const {
     NS_ASSERTION(aIndex < mResetCount, "out of range");
     return &mResets[aIndex];
   }
   nsresult  AllocateCounterResets(uint32_t aCount) {
     if (aCount != mResetCount) {
       DELETE_ARRAY_IF(mResets);
       if (aCount) {
         mResets = new nsStyleCounterData[aCount];
         if (! mResets) {
           mResetCount = 0;
           return NS_ERROR_OUT_OF_MEMORY;
         }
       }
       mResetCount = aCount;
     }
     return NS_OK;
   }
   nsresult  SetCounterResetAt(uint32_t aIndex, const nsString& aCounter, int32_t aValue) {
     if (aIndex < mResetCount) {
       mResets[aIndex].mCounter = aCounter;
       mResets[aIndex].mValue = aValue;
       return NS_OK;
     }
     return NS_ERROR_ILLEGAL_VALUE;
   }
   nsStyleCoord  mMarkerOffset;  // [reset] coord, auto
 protected:
   nsStyleContentData* mContents;
   nsStyleCounterData* mIncrements;
   nsStyleCounterData* mResets;
   uint32_t            mContentCount;
   uint32_t            mIncrementCount;
   uint32_t            mResetCount;
 };
 struct nsStyleUIReset {
   nsStyleUIReset(void);
   nsStyleUIReset(const nsStyleUIReset& aOther);
   ~nsStyleUIReset(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleUIReset();
     aContext->FreeToShell(sizeof(nsStyleUIReset), this);
   }
   nsChangeHint CalcDifference(const nsStyleUIReset& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   uint8_t   mUserSelect;      // [reset] (selection-style)
   uint8_t   mForceBrokenImageIcon; // [reset]  (0 if not forcing, otherwise forcing)
   uint8_t   mIMEMode;         // [reset]
   uint8_t   mWindowShadow;    // [reset]
 };
 struct nsCursorImage {
   bool mHaveHotspot;
   float mHotspotX, mHotspotY;
   nsCursorImage();
   nsCursorImage(const nsCursorImage& aOther);
   ~nsCursorImage();
   nsCursorImage& operator=(const nsCursorImage& aOther);
   /*
    * We hide mImage and force access through the getter and setter so that we
    * can lock the images we use. Cursor images are likely to be small, so we
    * don't care about discarding them. See bug 512260.
    * */
   void SetImage(imgIRequest *aImage) {
     if (mImage)
       mImage->UnlockImage();
     mImage = aImage;
     if (mImage)
       mImage->LockImage();
   }
   imgIRequest* GetImage() const {
     return mImage;
   }
 private:
   nsCOMPtr<imgIRequest> mImage;
 };
 struct nsStyleUserInterface {
   nsStyleUserInterface(void);
   nsStyleUserInterface(const nsStyleUserInterface& aOther);
   ~nsStyleUserInterface(void);
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleUserInterface();
     aContext->FreeToShell(sizeof(nsStyleUserInterface), this);
   }
   nsChangeHint CalcDifference(const nsStyleUserInterface& aOther) const;
   static nsChangeHint MaxDifference() {
     return nsChangeHint(nsChangeHint_UpdateCursor | NS_STYLE_HINT_FRAMECHANGE);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   uint8_t   mUserInput;       // [inherited]
   uint8_t   mUserModify;      // [inherited] (modify-content)
   uint8_t   mUserFocus;       // [inherited] (auto-select)
   uint8_t   mCursor;          // [inherited] See nsStyleConsts.h
   uint32_t mCursorArrayLength;
   nsCursorImage *mCursorArray;// [inherited] The specified URL values
                               //   and coordinates.  Takes precedence over
                               //   mCursor.  Zero-length array is represented
                               //   by null pointer.
   // Does not free mCursorArray; the caller is responsible for calling
   // |delete [] mCursorArray| first if it is needed.
   void CopyCursorArrayFrom(const nsStyleUserInterface& aSource);
 };
 struct nsStyleXUL {
   nsStyleXUL();
   nsStyleXUL(const nsStyleXUL& aSource);
   ~nsStyleXUL();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleXUL();
     aContext->FreeToShell(sizeof(nsStyleXUL), this);
   }
   nsChangeHint CalcDifference(const nsStyleXUL& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   float         mBoxFlex;               // [reset] see nsStyleConsts.h
   uint32_t      mBoxOrdinal;            // [reset] see nsStyleConsts.h
   uint8_t       mBoxAlign;              // [reset] see nsStyleConsts.h
   uint8_t       mBoxDirection;          // [reset] see nsStyleConsts.h
   uint8_t       mBoxOrient;             // [reset] see nsStyleConsts.h
   uint8_t       mBoxPack;               // [reset] see nsStyleConsts.h
   bool          mStretchStack;          // [reset] see nsStyleConsts.h
 };
 struct nsStyleColumn {
   nsStyleColumn(nsPresContext* aPresContext);
   nsStyleColumn(const nsStyleColumn& aSource);
   ~nsStyleColumn();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleColumn();
     aContext->FreeToShell(sizeof(nsStyleColumn), this);
   }
   nsChangeHint CalcDifference(const nsStyleColumn& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_STYLE_HINT_FRAMECHANGE;
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   /**
    * This is the maximum number of columns we can process. It's used in both
    * nsColumnSetFrame and nsRuleNode.
    */
   static const uint32_t kMaxColumnCount;
   uint32_t     mColumnCount; // [reset] see nsStyleConsts.h
   nsStyleCoord mColumnWidth; // [reset] coord, auto
   nsStyleCoord mColumnGap;   // [reset] coord, normal
   nscolor      mColumnRuleColor;  // [reset]
   uint8_t      mColumnRuleStyle;  // [reset]
   uint8_t      mColumnFill;  // [reset] see nsStyleConsts.h
   // See https://bugzilla.mozilla.org/show_bug.cgi?id=271586#c43 for why
   // this is hard to replace with 'currentColor'.
   bool mColumnRuleColorIsForeground;
   void SetColumnRuleWidth(nscoord aWidth) {
     mColumnRuleWidth = NS_ROUND_BORDER_TO_PIXELS(aWidth, mTwipsPerPixel);
   }
   nscoord GetComputedColumnRuleWidth() const {
     return (IsVisibleBorderStyle(mColumnRuleStyle) ? mColumnRuleWidth : 0);
   }
 protected:
   nscoord mColumnRuleWidth;  // [reset] coord
   nscoord mTwipsPerPixel;
 };
 enum nsStyleSVGPaintType {
   eStyleSVGPaintType_None = 1,
   eStyleSVGPaintType_Color,
   eStyleSVGPaintType_Server,
   eStyleSVGPaintType_ContextFill,
   eStyleSVGPaintType_ContextStroke
 };
 enum nsStyleSVGOpacitySource {
   eStyleSVGOpacitySource_Normal,
   eStyleSVGOpacitySource_ContextFillOpacity,
   eStyleSVGOpacitySource_ContextStrokeOpacity
 };
 struct nsStyleSVGPaint
 {
   union {
     nscolor mColor;
     nsIURI *mPaintServer;
   } mPaint;
   nsStyleSVGPaintType mType;
   nscolor mFallbackColor;
   nsStyleSVGPaint() : mType(nsStyleSVGPaintType(0)) { mPaint.mPaintServer = nullptr; }
   ~nsStyleSVGPaint();
   void SetType(nsStyleSVGPaintType aType);
   nsStyleSVGPaint& operator=(const nsStyleSVGPaint& aOther);
   bool operator==(const nsStyleSVGPaint& aOther) const;
   bool operator!=(const nsStyleSVGPaint& aOther) const {
     return !(*this == aOther);
   }
 };
 struct nsStyleSVG {
   nsStyleSVG();
   nsStyleSVG(const nsStyleSVG& aSource);
   ~nsStyleSVG();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleSVG();
     aContext->FreeToShell(sizeof(nsStyleSVG), this);
   }
   nsChangeHint CalcDifference(const nsStyleSVG& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_CombineHint(NS_CombineHint(nsChangeHint_UpdateEffects,
              NS_CombineHint(nsChangeHint_NeedReflow, nsChangeHint_NeedDirtyReflow)), // XXX remove nsChangeHint_NeedDirtyReflow: bug 876085
                                          nsChangeHint_RepaintFrame);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow as an inherited hint
     // and never returns nsChangeHint_ClearAncestorIntrinsics at all.
     return nsChangeHint_NeedReflow;
   }
   nsStyleSVGPaint  mFill;             // [inherited]
   nsStyleSVGPaint  mStroke;           // [inherited]
   nsCOMPtr<nsIURI> mMarkerEnd;        // [inherited]
   nsCOMPtr<nsIURI> mMarkerMid;        // [inherited]
   nsCOMPtr<nsIURI> mMarkerStart;      // [inherited]
   nsStyleCoord    *mStrokeDasharray;  // [inherited] coord, percent, factor
   nsStyleCoord     mStrokeDashoffset; // [inherited] coord, percent, factor
   nsStyleCoord     mStrokeWidth;      // [inherited] coord, percent, factor
   float            mFillOpacity;      // [inherited]
   float            mStrokeMiterlimit; // [inherited]
   float            mStrokeOpacity;    // [inherited]
   uint32_t         mStrokeDasharrayLength;
   uint8_t          mClipRule;         // [inherited]
   uint8_t          mColorInterpolation; // [inherited] see nsStyleConsts.h
   uint8_t          mColorInterpolationFilters; // [inherited] see nsStyleConsts.h
   uint8_t          mFillRule;         // [inherited] see nsStyleConsts.h
   uint8_t          mImageRendering;   // [inherited] see nsStyleConsts.h
   uint8_t          mPaintOrder;       // [inherited] see nsStyleConsts.h
   uint8_t          mShapeRendering;   // [inherited] see nsStyleConsts.h
   uint8_t          mStrokeLinecap;    // [inherited] see nsStyleConsts.h
   uint8_t          mStrokeLinejoin;   // [inherited] see nsStyleConsts.h
   uint8_t          mTextAnchor;       // [inherited] see nsStyleConsts.h
   uint8_t          mTextRendering;    // [inherited] see nsStyleConsts.h
   // In SVG glyphs, whether we inherit fill or stroke opacity from the outer
   // text object.
   // Use 3 bits to avoid signedness problems in MSVC.
   nsStyleSVGOpacitySource mFillOpacitySource    : 3;
   nsStyleSVGOpacitySource mStrokeOpacitySource  : 3;
   // SVG glyph outer object inheritance for other properties
   bool mStrokeDasharrayFromObject   : 1;
   bool mStrokeDashoffsetFromObject  : 1;
   bool mStrokeWidthFromObject       : 1;
   bool HasMarker() const {
     return mMarkerStart || mMarkerMid || mMarkerEnd;
   }
   /**
    * Returns true if the stroke is not "none" and the stroke-opacity is greater
    * than zero. This ignores stroke-widths as that depends on the context.
    */
   bool HasStroke() const {
     return mStroke.mType != eStyleSVGPaintType_None && mStrokeOpacity > 0;
   }
   /**
    * Returns true if the fill is not "none" and the fill-opacity is greater
    * than zero.
    */
   bool HasFill() const {
     return mFill.mType != eStyleSVGPaintType_None && mFillOpacity > 0;
   }
 };
 struct nsStyleFilter {
   nsStyleFilter();
   nsStyleFilter(const nsStyleFilter& aSource);
   ~nsStyleFilter();
   nsStyleFilter& operator=(const nsStyleFilter& aOther);
   bool operator==(const nsStyleFilter& aOther) const;
   int32_t GetType() const {
     return mType;
   }
   const nsStyleCoord& GetFilterParameter() const {
     NS_ASSERTION(mType != NS_STYLE_FILTER_DROP_SHADOW &&
                  mType != NS_STYLE_FILTER_URL &&
                  mType != NS_STYLE_FILTER_NONE, "wrong filter type");
     return mFilterParameter;
   }
   void SetFilterParameter(const nsStyleCoord& aFilterParameter,
                           int32_t aType);
   nsIURI* GetURL() const {
     NS_ASSERTION(mType == NS_STYLE_FILTER_URL, "wrong filter type");
     return mURL;
   }
   void SetURL(nsIURI* aURL);
   nsCSSShadowArray* GetDropShadow() const {
     NS_ASSERTION(mType == NS_STYLE_FILTER_DROP_SHADOW, "wrong filter type");
     return mDropShadow;
   }
   void SetDropShadow(nsCSSShadowArray* aDropShadow);
 private:
   void ReleaseRef();
   int32_t mType; // see NS_STYLE_FILTER_* constants in nsStyleConsts.h
   nsStyleCoord mFilterParameter; // coord, percent, factor, angle
   union {
     nsIURI* mURL;
     nsCSSShadowArray* mDropShadow;
   };
 };
 template<>
 struct nsTArray_CopyChooser<nsStyleFilter> {
   typedef nsTArray_CopyWithConstructors<nsStyleFilter> Type;
 };
 struct nsStyleSVGReset {
   nsStyleSVGReset();
   nsStyleSVGReset(const nsStyleSVGReset& aSource);
   ~nsStyleSVGReset();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleSVGReset();
     aContext->FreeToShell(sizeof(nsStyleSVGReset), this);
   }
   nsChangeHint CalcDifference(const nsStyleSVGReset& aOther) const;
   static nsChangeHint MaxDifference() {
     return NS_CombineHint(nsChangeHint_UpdateEffects,
             NS_CombineHint(nsChangeHint_UpdateOverflow, NS_STYLE_HINT_REFLOW));
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics as inherited hints.
     return NS_CombineHint(nsChangeHint_NeedReflow,
                           nsChangeHint_ClearAncestorIntrinsics);
   }
   bool HasFilters() const {
     return mFilters.Length() > 0;
   }
   nsCOMPtr<nsIURI> mClipPath;         // [reset]
   nsTArray<nsStyleFilter> mFilters;   // [reset]
   nsCOMPtr<nsIURI> mMask;             // [reset]
   nscolor          mStopColor;        // [reset]
   nscolor          mFloodColor;       // [reset]
   nscolor          mLightingColor;    // [reset]
   float            mStopOpacity;      // [reset]
   float            mFloodOpacity;     // [reset]
   uint8_t          mDominantBaseline; // [reset] see nsStyleConsts.h
   uint8_t          mVectorEffect;     // [reset] see nsStyleConsts.h
   uint8_t          mMaskType;         // [reset] see nsStyleConsts.h
 };
 struct nsStyleVariables {
   nsStyleVariables();
   nsStyleVariables(const nsStyleVariables& aSource);
   ~nsStyleVariables();
   void* operator new(size_t sz, nsPresContext* aContext) CPP_THROW_NEW {
     return aContext->AllocateFromShell(sz);
   }
   void Destroy(nsPresContext* aContext) {
     this->~nsStyleVariables();
     aContext->FreeToShell(sizeof(nsStyleVariables), this);
   }
   nsChangeHint CalcDifference(const nsStyleVariables& aOther) const;
   static nsChangeHint MaxDifference() {
     return nsChangeHint(0);
   }
   static nsChangeHint MaxDifferenceNeverInherited() {
     // CalcDifference never returns nsChangeHint_NeedReflow or
     // nsChangeHint_ClearAncestorIntrinsics at all.
     return nsChangeHint(0);
   }
   mozilla::CSSVariableValues mVariables;
 };
 #endif /* nsStyleStruct_h___ */

The Tor Browser / annotate

layout/style/nsStyleStruct.h@deefc01c0e14 (annotated)

layout/style/nsStyleStruct.h