diff -r 000000000000 -r 6474c204b198 layout/xul/tree/nsTreeBodyFrame.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/xul/tree/nsTreeBodyFrame.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,634 @@
+/* -*- 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/. */
+
+#ifndef nsTreeBodyFrame_h
+#define nsTreeBodyFrame_h
+
+#include "mozilla/Attributes.h"
+
+#include "nsLeafBoxFrame.h"
+#include "nsITreeView.h"
+#include "nsICSSPseudoComparator.h"
+#include "nsIScrollbarMediator.h"
+#include "nsITimer.h"
+#include "nsIReflowCallback.h"
+#include "nsTArray.h"
+#include "nsTreeStyleCache.h"
+#include "nsTreeColumns.h"
+#include "nsAutoPtr.h"
+#include "nsDataHashtable.h"
+#include "imgIRequest.h"
+#include "imgINotificationObserver.h"
+#include "nsScrollbarFrame.h"
+#include "nsThreadUtils.h"
+#include "mozilla/LookAndFeel.h"
+#include "nsIScrollbarOwner.h"
+
+class nsOverflowChecker;
+class nsTreeImageListener;
+
+namespace mozilla {
+namespace layout {
+class ScrollbarActivity;
+}
+}
+
+// An entry in the tree's image cache
+struct nsTreeImageCacheEntry
+{
+  nsTreeImageCacheEntry() {}
+  nsTreeImageCacheEntry(imgIRequest *aRequest, imgINotificationObserver *aListener)
+    : request(aRequest), listener(aListener) {}
+
+  nsCOMPtr<imgIRequest> request;
+  nsCOMPtr<imgINotificationObserver> listener;
+};
+
+// The actual frame that paints the cells and rows.
+class nsTreeBodyFrame MOZ_FINAL
+  : public nsLeafBoxFrame
+  , public nsICSSPseudoComparator
+  , public nsIScrollbarMediator
+  , public nsIReflowCallback
+  , public nsIScrollbarOwner
+{
+public:
+  typedef mozilla::layout::ScrollbarActivity ScrollbarActivity;
+
+  nsTreeBodyFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
+  ~nsTreeBodyFrame();
+
+  NS_DECL_QUERYFRAME_TARGET(nsTreeBodyFrame)
+  NS_DECL_QUERYFRAME
+  NS_DECL_FRAMEARENA_HELPERS
+
+  // Callback handler methods for refresh driver based animations.
+  // Calls to these functions are forwarded from nsTreeImageListener. These
+  // mirror how nsImageFrame works.
+  nsresult OnImageIsAnimated(imgIRequest* aRequest);
+
+  // non-virtual signatures like nsITreeBodyFrame
+  already_AddRefed<nsTreeColumns> Columns() const
+  {
+    nsRefPtr<nsTreeColumns> cols = mColumns;
+    return cols.forget();
+  }
+  already_AddRefed<nsITreeView> GetExistingView() const
+  {
+    nsCOMPtr<nsITreeView> view = mView;
+    return view.forget();
+  }
+  nsresult GetView(nsITreeView **aView);
+  nsresult SetView(nsITreeView *aView);
+  nsresult GetFocused(bool *aFocused);
+  nsresult SetFocused(bool aFocused);
+  nsresult GetTreeBody(nsIDOMElement **aElement);
+  nsresult GetRowHeight(int32_t *aValue);
+  nsresult GetRowWidth(int32_t *aValue);
+  nsresult GetHorizontalPosition(int32_t *aValue);
+  nsresult GetSelectionRegion(nsIScriptableRegion **aRegion);
+  int32_t FirstVisibleRow() const { return mTopRowIndex; }
+  int32_t LastVisibleRow() const { return mTopRowIndex + mPageLength; }
+  int32_t PageLength() const { return mPageLength; }
+  nsresult EnsureRowIsVisible(int32_t aRow);
+  nsresult EnsureCellIsVisible(int32_t aRow, nsITreeColumn *aCol);
+  nsresult ScrollToRow(int32_t aRow);
+  nsresult ScrollByLines(int32_t aNumLines);
+  nsresult ScrollByPages(int32_t aNumPages);
+  nsresult ScrollToCell(int32_t aRow, nsITreeColumn *aCol);
+  nsresult ScrollToColumn(nsITreeColumn *aCol);
+  nsresult ScrollToHorizontalPosition(int32_t aValue);
+  nsresult Invalidate();
+  nsresult InvalidateColumn(nsITreeColumn *aCol);
+  nsresult InvalidateRow(int32_t aRow);
+  nsresult InvalidateCell(int32_t aRow, nsITreeColumn *aCol);
+  nsresult InvalidateRange(int32_t aStart, int32_t aEnd);
+  nsresult InvalidateColumnRange(int32_t aStart, int32_t aEnd,
+                                 nsITreeColumn *aCol);
+  nsresult GetRowAt(int32_t aX, int32_t aY, int32_t *aValue);
+  nsresult GetCellAt(int32_t aX, int32_t aY, int32_t *aRow,
+                     nsITreeColumn **aCol, nsACString &aChildElt);
+  nsresult GetCoordsForCellItem(int32_t aRow, nsITreeColumn *aCol,
+                                const nsACString &aElt,
+                                int32_t *aX, int32_t *aY,
+                                int32_t *aWidth, int32_t *aHeight);
+  nsresult IsCellCropped(int32_t aRow, nsITreeColumn *aCol, bool *aResult);
+  nsresult RowCountChanged(int32_t aIndex, int32_t aCount);
+  nsresult BeginUpdateBatch();
+  nsresult EndUpdateBatch();
+  nsresult ClearStyleAndImageCaches();
+
+  void ManageReflowCallback(const nsRect& aRect, nscoord aHorzWidth);
+
+  virtual nsSize GetMinSize(nsBoxLayoutState& aBoxLayoutState) MOZ_OVERRIDE;
+  virtual void SetBounds(nsBoxLayoutState& aBoxLayoutState, const nsRect& aRect,
+                         bool aRemoveOverflowArea = false) MOZ_OVERRIDE;
+
+  // nsIReflowCallback
+  virtual bool ReflowFinished() MOZ_OVERRIDE;
+  virtual void ReflowCallbackCanceled() MOZ_OVERRIDE;
+
+  // nsICSSPseudoComparator
+  virtual bool PseudoMatches(nsCSSSelector* aSelector) MOZ_OVERRIDE;
+
+  // nsIScrollbarMediator
+  NS_IMETHOD PositionChanged(nsScrollbarFrame* aScrollbar, int32_t aOldIndex, int32_t& aNewIndex) MOZ_OVERRIDE;
+  NS_IMETHOD ScrollbarButtonPressed(nsScrollbarFrame* aScrollbar, int32_t aOldIndex, int32_t aNewIndex) MOZ_OVERRIDE;
+  NS_IMETHOD VisibilityChanged(bool aVisible) MOZ_OVERRIDE { Invalidate(); return NS_OK; }
+
+  // nsIScrollbarOwner
+  virtual nsIFrame* GetScrollbarBox(bool aVertical) MOZ_OVERRIDE {
+    ScrollParts parts = GetScrollParts();
+    return aVertical ? parts.mVScrollbar : parts.mHScrollbar;
+  }
+
+  // Overridden from nsIFrame to cache our pres context.
+  virtual void Init(nsIContent*     aContent,
+                    nsIFrame*       aParent,
+                    nsIFrame*       aPrevInFlow) MOZ_OVERRIDE;
+  virtual void DestroyFrom(nsIFrame* aDestructRoot) MOZ_OVERRIDE;
+
+  virtual nsresult GetCursor(const nsPoint& aPoint,
+                             nsIFrame::Cursor& aCursor) MOZ_OVERRIDE;
+
+  virtual nsresult HandleEvent(nsPresContext* aPresContext,
+                               mozilla::WidgetGUIEvent* aEvent,
+                               nsEventStatus* aEventStatus) MOZ_OVERRIDE;
+
+  virtual void BuildDisplayList(nsDisplayListBuilder*   aBuilder,
+                                const nsRect&           aDirtyRect,
+                                const nsDisplayListSet& aLists) MOZ_OVERRIDE;
+
+  virtual void DidSetStyleContext(nsStyleContext* aOldStyleContext) MOZ_OVERRIDE;
+
+  friend nsIFrame* NS_NewTreeBodyFrame(nsIPresShell* aPresShell);
+  friend class nsTreeColumn;
+
+  struct ScrollParts {
+    nsScrollbarFrame*    mVScrollbar;
+    nsCOMPtr<nsIContent> mVScrollbarContent;
+    nsScrollbarFrame*    mHScrollbar;
+    nsCOMPtr<nsIContent> mHScrollbarContent;
+    nsIFrame*            mColumnsFrame;
+    nsIScrollableFrame*  mColumnsScrollFrame;
+  };
+
+  void PaintTreeBody(nsRenderingContext& aRenderingContext,
+                     const nsRect& aDirtyRect, nsPoint aPt);
+
+  nsITreeBoxObject* GetTreeBoxObject() const { return mTreeBoxObject; }
+
+  // Get the base element, <tree> or <select>
+  nsIContent* GetBaseElement();
+
+  bool GetVerticalOverflow() const { return mVerticalOverflow; }
+  bool GetHorizontalOverflow() const {return mHorizontalOverflow; }
+
+protected:
+  friend class nsOverflowChecker;
+
+  // This method paints a specific column background of the tree.
+  void PaintColumn(nsTreeColumn*        aColumn,
+                   const nsRect&        aColumnRect,
+                   nsPresContext*      aPresContext,
+                   nsRenderingContext& aRenderingContext,
+                   const nsRect&        aDirtyRect);
+
+  // This method paints a single row in the tree.
+  void PaintRow(int32_t              aRowIndex,
+                const nsRect&        aRowRect,
+                nsPresContext*       aPresContext,
+                nsRenderingContext& aRenderingContext,
+                const nsRect&        aDirtyRect,
+                nsPoint              aPt);
+
+  // This method paints a single separator in the tree.
+  void PaintSeparator(int32_t              aRowIndex,
+                      const nsRect&        aSeparatorRect,
+                      nsPresContext*      aPresContext,
+                      nsRenderingContext& aRenderingContext,
+                      const nsRect&        aDirtyRect);
+
+  // This method paints a specific cell in a given row of the tree.
+  void PaintCell(int32_t              aRowIndex, 
+                 nsTreeColumn*        aColumn,
+                 const nsRect&        aCellRect,
+                 nsPresContext*       aPresContext,
+                 nsRenderingContext& aRenderingContext,
+                 const nsRect&        aDirtyRect,
+                 nscoord&             aCurrX,
+                 nsPoint              aPt);
+
+  // This method paints the twisty inside a cell in the primary column of an tree.
+  void PaintTwisty(int32_t              aRowIndex,
+                   nsTreeColumn*        aColumn,
+                   const nsRect&        aTwistyRect,
+                   nsPresContext*      aPresContext,
+                   nsRenderingContext& aRenderingContext,
+                   const nsRect&        aDirtyRect,
+                   nscoord&             aRemainingWidth,
+                   nscoord&             aCurrX);
+
+  // This method paints the image inside the cell of an tree.
+  void PaintImage(int32_t              aRowIndex,
+                  nsTreeColumn*        aColumn,
+                  const nsRect&        aImageRect,
+                  nsPresContext*      aPresContext,
+                  nsRenderingContext& aRenderingContext,
+                  const nsRect&        aDirtyRect,
+                  nscoord&             aRemainingWidth,
+                  nscoord&             aCurrX);
+
+  // This method paints the text string inside a particular cell of the tree.
+  void PaintText(int32_t              aRowIndex, 
+                 nsTreeColumn*        aColumn,
+                 const nsRect&        aTextRect,
+                 nsPresContext*      aPresContext,
+                 nsRenderingContext& aRenderingContext,
+                 const nsRect&        aDirtyRect,
+                 nscoord&             aCurrX);
+
+  // This method paints the checkbox inside a particular cell of the tree.
+  void PaintCheckbox(int32_t              aRowIndex, 
+                     nsTreeColumn*        aColumn,
+                     const nsRect&        aCheckboxRect,
+                     nsPresContext*      aPresContext,
+                     nsRenderingContext& aRenderingContext,
+                     const nsRect&        aDirtyRect);
+
+  // This method paints the progress meter inside a particular cell of the tree.
+  void PaintProgressMeter(int32_t              aRowIndex, 
+                          nsTreeColumn*        aColumn,
+                          const nsRect&        aProgressMeterRect,
+                          nsPresContext*      aPresContext,
+                          nsRenderingContext& aRenderingContext,
+                          const nsRect&        aDirtyRect);
+
+  // This method paints a drop feedback of the tree.
+  void PaintDropFeedback(const nsRect&        aDropFeedbackRect, 
+                         nsPresContext*      aPresContext,
+                         nsRenderingContext& aRenderingContext,
+                         const nsRect&        aDirtyRect,
+                         nsPoint              aPt);
+
+  // This method is called with a specific style context and rect to
+  // paint the background rect as if it were a full-blown frame.
+  void PaintBackgroundLayer(nsStyleContext*      aStyleContext,
+                            nsPresContext*      aPresContext, 
+                            nsRenderingContext& aRenderingContext, 
+                            const nsRect&        aRect,
+                            const nsRect&        aDirtyRect);
+
+
+  // An internal hit test.  aX and aY are expected to be in twips in the
+  // coordinate system of this frame.
+  int32_t GetRowAt(nscoord aX, nscoord aY);
+
+  // Check for bidi characters in the text, and if there are any, ensure
+  // that the prescontext is in bidi mode.
+  void CheckTextForBidi(nsAutoString& aText);
+
+  void AdjustForCellText(nsAutoString& aText,
+                         int32_t aRowIndex,  nsTreeColumn* aColumn,
+                         nsRenderingContext& aRenderingContext,
+                         nsRect& aTextRect);
+
+  // A helper used when hit testing.
+  nsIAtom* GetItemWithinCellAt(nscoord aX, const nsRect& aCellRect,
+                               int32_t aRowIndex, nsTreeColumn* aColumn);
+
+  // An internal hit test.  aX and aY are expected to be in twips in the
+  // coordinate system of this frame.
+  void GetCellAt(nscoord aX, nscoord aY, int32_t* aRow, nsTreeColumn** aCol,
+                 nsIAtom** aChildElt);
+
+  // Retrieve the area for the twisty for a cell.
+  nsITheme* GetTwistyRect(int32_t aRowIndex,
+                          nsTreeColumn* aColumn,
+                          nsRect& aImageRect,
+                          nsRect& aTwistyRect,
+                          nsPresContext* aPresContext,
+                          nsRenderingContext& aRenderingContext,
+                          nsStyleContext* aTwistyContext);
+
+  // Fetch an image from the image cache.
+  nsresult GetImage(int32_t aRowIndex, nsTreeColumn* aCol, bool aUseContext,
+                    nsStyleContext* aStyleContext, bool& aAllowImageRegions, imgIContainer** aResult);
+
+  // Returns the size of a given image.   This size *includes* border and
+  // padding.  It does not include margins.
+  nsRect GetImageSize(int32_t aRowIndex, nsTreeColumn* aCol, bool aUseContext, nsStyleContext* aStyleContext);
+
+  // Returns the destination size of the image, not including borders and padding.
+  nsSize GetImageDestSize(nsStyleContext* aStyleContext, bool useImageRegion, imgIContainer* image);
+
+  // Returns the source rectangle of the image to be displayed.
+  nsRect GetImageSourceRect(nsStyleContext* aStyleContext, bool useImageRegion, imgIContainer* image);
+
+  // Returns the height of rows in the tree.
+  int32_t GetRowHeight();
+
+  // Returns our indentation width.
+  int32_t GetIndentation();
+
+  // Calculates our width/height once border and padding have been removed.
+  void CalcInnerBox();
+
+  // Calculate the total width of our scrollable portion
+  nscoord CalcHorzWidth(const ScrollParts& aParts);
+
+  // Looks up a style context in the style cache.  On a cache miss we resolve
+  // the pseudo-styles passed in and place them into the cache.
+  nsStyleContext* GetPseudoStyleContext(nsIAtom* aPseudoElement);
+
+  // Retrieves the scrollbars and scrollview relevant to this treebody. We
+  // traverse the frame tree under our base element, in frame order, looking
+  // for the first relevant vertical scrollbar, horizontal scrollbar, and
+  // scrollable frame (with associated content and scrollable view). These
+  // are all volatile and should not be retained.
+  ScrollParts GetScrollParts();
+
+  // Update the curpos of the scrollbar.
+  void UpdateScrollbars(const ScrollParts& aParts);
+
+  // Update the maxpos of the scrollbar.
+  void InvalidateScrollbars(const ScrollParts& aParts, nsWeakFrame& aWeakColumnsFrame);
+
+  // Check overflow and generate events.
+  void CheckOverflow(const ScrollParts& aParts);
+
+  // Calls UpdateScrollbars, Invalidate aNeedsFullInvalidation if true,
+  // InvalidateScrollbars and finally CheckOverflow.
+  // returns true if the frame is still alive after the method call.
+  bool FullScrollbarsUpdate(bool aNeedsFullInvalidation);
+
+  // Use to auto-fill some of the common properties without the view having to do it.
+  // Examples include container, open, selected, and focus.
+  void PrefillPropertyArray(int32_t aRowIndex, nsTreeColumn* aCol);
+
+  // Our internal scroll method, used by all the public scroll methods.
+  nsresult ScrollInternal(const ScrollParts& aParts, int32_t aRow);
+  nsresult ScrollToRowInternal(const ScrollParts& aParts, int32_t aRow);
+  nsresult ScrollToColumnInternal(const ScrollParts& aParts, nsITreeColumn* aCol);
+  nsresult ScrollHorzInternal(const ScrollParts& aParts, int32_t aPosition);
+  nsresult EnsureRowIsVisibleInternal(const ScrollParts& aParts, int32_t aRow);
+
+  // Convert client pixels into appunits in our coordinate space.
+  nsPoint AdjustClientCoordsToBoxCoordSpace(int32_t aX, int32_t aY);
+
+  // Cache the box object
+  void EnsureBoxObject();
+
+  void EnsureView();
+
+  nsresult GetCellWidth(int32_t aRow, nsTreeColumn* aCol,
+                        nsRenderingContext* aRenderingContext,
+                        nscoord& aDesiredSize, nscoord& aCurrentSize);
+  nscoord CalcMaxRowWidth();
+
+  // Translate the given rect horizontally from tree coordinates into the
+  // coordinate system of our nsTreeBodyFrame.  If clip is true, then clip the
+  // rect to its intersection with mInnerBox in the horizontal direction.
+  // Return whether the result has a nonempty intersection with mInnerBox
+  // after projecting both onto the horizontal coordinate axis.
+  bool OffsetForHorzScroll(nsRect& rect, bool clip);
+
+  bool CanAutoScroll(int32_t aRowIndex);
+
+  // Calc the row and above/below/on status given where the mouse currently is hovering.
+  // Also calc if we're in the region in which we want to auto-scroll the tree.
+  // A positive value of |aScrollLines| means scroll down, a negative value
+  // means scroll up, a zero value means that we aren't in drag scroll region.
+  void ComputeDropPosition(mozilla::WidgetGUIEvent* aEvent,
+                           int32_t* aRow,
+                           int16_t* aOrient,
+                           int16_t* aScrollLines);
+
+  // Mark ourselves dirty if we're a select widget
+  void MarkDirtyIfSelect();
+
+  void InvalidateDropFeedback(int32_t aRow, int16_t aOrientation) {
+    InvalidateRow(aRow);
+    if (aOrientation != nsITreeView::DROP_ON)
+      InvalidateRow(aRow + aOrientation);
+  }
+
+public:
+  static
+  already_AddRefed<nsTreeColumn> GetColumnImpl(nsITreeColumn* aUnknownCol) {
+    if (!aUnknownCol)
+      return nullptr;
+
+    nsCOMPtr<nsTreeColumn> col = do_QueryInterface(aUnknownCol);
+    return col.forget();
+  }
+
+  /**
+   * Remove an nsITreeImageListener from being tracked by this frame. Only tree
+   * image listeners that are created by this frame are tracked.
+   *
+   * @param aListener A pointer to an nsTreeImageListener to no longer
+   *        track.
+   */
+  void RemoveTreeImageListener(nsTreeImageListener* aListener);
+
+protected:
+
+  // Create a new timer. This method is used to delay various actions like
+  // opening/closing folders or tree scrolling.
+  // aID is type of the action, aFunc is the function to be called when
+  // the timer fires and aType is type of timer - one shot or repeating.
+  nsresult CreateTimer(const mozilla::LookAndFeel::IntID aID,
+                       nsTimerCallbackFunc aFunc, int32_t aType,
+                       nsITimer** aTimer);
+
+  static void OpenCallback(nsITimer *aTimer, void *aClosure);
+
+  static void CloseCallback(nsITimer *aTimer, void *aClosure);
+
+  static void LazyScrollCallback(nsITimer *aTimer, void *aClosure);
+
+  static void ScrollCallback(nsITimer *aTimer, void *aClosure);
+
+  class ScrollEvent : public nsRunnable {
+  public:
+    NS_DECL_NSIRUNNABLE
+    ScrollEvent(nsTreeBodyFrame *aInner) : mInner(aInner) {}
+    void Revoke() { mInner = nullptr; }
+  private:
+    nsTreeBodyFrame* mInner;
+  };
+
+  void PostScrollEvent();
+  void FireScrollEvent();
+
+  virtual void ScrollbarActivityStarted() const MOZ_OVERRIDE;
+  virtual void ScrollbarActivityStopped() const MOZ_OVERRIDE;
+
+  /**
+   * Clear the pointer to this frame for all nsTreeImageListeners that were
+   * created by this frame.
+   */
+  void DetachImageListeners();
+
+#ifdef ACCESSIBILITY
+  /**
+   * Fires 'treeRowCountChanged' event asynchronously. The event supports
+   * nsIDOMCustomEvent interface that is used to expose the following
+   * information structures.
+   *
+   * @param aIndex  the row index rows are added/removed from
+   * @param aCount  the number of added/removed rows (the sign points to
+   *                an operation, plus - addition, minus - removing)
+   */
+  void FireRowCountChangedEvent(int32_t aIndex, int32_t aCount);
+
+  /**
+   * Fires 'treeInvalidated' event asynchronously. The event supports
+   * nsIDOMCustomEvent interface that is used to expose the information
+   * structures described by method arguments.
+   *
+   * @param aStartRow  the start index of invalidated rows, -1 means that
+   *                   columns have been invalidated only
+   * @param aEndRow    the end index of invalidated rows, -1 means that columns
+   *                   have been invalidated only
+   * @param aStartCol  the start invalidated column, nullptr means that only rows
+   *                   have been invalidated
+   * @param aEndCol    the end invalidated column, nullptr means that rows have
+   *                   been invalidated only
+   */
+  void FireInvalidateEvent(int32_t aStartRow, int32_t aEndRow,
+                           nsITreeColumn *aStartCol, nsITreeColumn *aEndCol);
+#endif
+
+protected: // Data Members
+
+  class Slots {
+    public:
+      Slots() {
+      }
+
+      ~Slots() {
+        if (mTimer)
+          mTimer->Cancel();
+      }
+
+      friend class nsTreeBodyFrame;
+
+    protected:
+      // If the drop is actually allowed here or not.
+      bool                     mDropAllowed;
+
+      // True while dragging over the tree.
+      bool mIsDragging;
+
+      // The row the mouse is hovering over during a drop.
+      int32_t                  mDropRow;
+
+      // Where we want to draw feedback (above/on this row/below) if allowed.
+      int16_t                  mDropOrient;
+
+      // Number of lines to be scrolled.
+      int16_t                  mScrollLines;
+
+      // The drag action that was received for this slot
+      uint32_t                 mDragAction;
+
+      // Timer for opening/closing spring loaded folders or scrolling the tree.
+      nsCOMPtr<nsITimer>       mTimer;
+
+      // An array used to keep track of all spring loaded folders.
+      nsTArray<int32_t>        mArray;
+  };
+
+  Slots* mSlots;
+
+  nsRevocableEventPtr<ScrollEvent> mScrollEvent;
+
+  nsRefPtr<ScrollbarActivity> mScrollbarActivity;
+
+  // The cached box object parent.
+  nsCOMPtr<nsITreeBoxObject> mTreeBoxObject;
+
+  // Cached column information.
+  nsRefPtr<nsTreeColumns> mColumns;
+
+  // The current view for this tree widget.  We get all of our row and cell data
+  // from the view.
+  nsCOMPtr<nsITreeView> mView;
+
+  // A cache of all the style contexts we have seen for rows and cells of the tree.  This is a mapping from
+  // a list of atoms to a corresponding style context.  This cache stores every combination that
+  // occurs in the tree, so for n distinct properties, this cache could have 2 to the n entries
+  // (the power set of all row properties).
+  nsTreeStyleCache mStyleCache;
+
+  // A hashtable that maps from URLs to image request/listener pairs.  The URL
+  // is provided by the view or by the style context. The style context
+  // represents a resolved :-moz-tree-cell-image (or twisty) pseudo-element.
+  // It maps directly to an imgIRequest.
+  nsDataHashtable<nsStringHashKey, nsTreeImageCacheEntry> mImageCache;
+
+  // A scratch array used when looking up cached style contexts.
+  AtomArray mScratchArray;
+
+  // The index of the first visible row and the # of rows visible onscreen.  
+  // The tree only examines onscreen rows, starting from
+  // this index and going up to index+pageLength.
+  int32_t mTopRowIndex;
+  int32_t mPageLength;
+
+  // The horizontal scroll position
+  nscoord mHorzPosition;
+
+  // The original desired horizontal width before changing it and posting a
+  // reflow callback. In some cases, the desired horizontal width can first be
+  // different from the current desired horizontal width, only to return to
+  // the same value later during the same reflow. In this case, we can cancel
+  // the posted reflow callback and prevent an unnecessary reflow.
+  nscoord mOriginalHorzWidth;
+  // Our desired horizontal width (the width for which we actually have tree
+  // columns).
+  nscoord mHorzWidth;
+  // The amount by which to adjust the width of the last cell.
+  // This depends on whether or not the columnpicker and scrollbars are present.
+  nscoord mAdjustWidth;
+
+  // Cached heights and indent info.
+  nsRect mInnerBox; // 4-byte aligned
+  int32_t mRowHeight;
+  int32_t mIndentation;
+  nscoord mStringWidth;
+
+  int32_t mUpdateBatchNest;
+
+  // Cached row count.
+  int32_t mRowCount;
+
+  // The row the mouse is hovering over.
+  int32_t mMouseOverRow;
+
+  // Whether or not we're currently focused.
+  bool mFocused;
+
+  // Do we have a fixed number of onscreen rows?
+  bool mHasFixedRowCount;
+
+  bool mVerticalOverflow;
+  bool mHorizontalOverflow;
+
+  bool mReflowCallbackPosted;
+
+  // Set while we flush layout to take account of effects of
+  // overflow/underflow event handlers
+  bool mCheckingOverflow;
+
+  // Hash table to keep track of which listeners we created and thus
+  // have pointers to us.
+  nsTHashtable<nsPtrHashKey<nsTreeImageListener> > mCreatedListeners;
+
+}; // class nsTreeBodyFrame
+
+#endif