diff -r 000000000000 -r 6474c204b198 layout/generic/nsBRFrame.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/generic/nsBRFrame.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,261 @@
+/* -*- 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/. */
+
+/* rendering object for HTML <br> elements */
+
+#include "nsCOMPtr.h"
+#include "nsFrame.h"
+#include "nsPresContext.h"
+#include "nsLineLayout.h"
+#include "nsStyleConsts.h"
+#include "nsGkAtoms.h"
+#include "nsRenderingContext.h"
+#include "nsLayoutUtils.h"
+
+//FOR SELECTION
+#include "nsIContent.h"
+//END INCLUDES FOR SELECTION
+
+using namespace mozilla;
+
+class BRFrame : public nsFrame {
+public:
+  NS_DECL_FRAMEARENA_HELPERS
+
+  friend nsIFrame* NS_NewBRFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
+
+  virtual ContentOffsets CalcContentOffsetsFromFramePoint(nsPoint aPoint) MOZ_OVERRIDE;
+
+  virtual FrameSearchResult PeekOffsetNoAmount(bool aForward, int32_t* aOffset) MOZ_OVERRIDE;
+  virtual FrameSearchResult PeekOffsetCharacter(bool aForward, int32_t* aOffset,
+                                     bool aRespectClusters = true) MOZ_OVERRIDE;
+  virtual FrameSearchResult PeekOffsetWord(bool aForward, bool aWordSelectEatSpace,
+                              bool aIsKeyboardSelect, int32_t* aOffset,
+                              PeekWordState* aState) MOZ_OVERRIDE;
+
+  virtual nsresult Reflow(nsPresContext* aPresContext,
+                          nsHTMLReflowMetrics& aDesiredSize,
+                          const nsHTMLReflowState& aReflowState,
+                          nsReflowStatus& aStatus) MOZ_OVERRIDE;
+  virtual void AddInlineMinWidth(nsRenderingContext *aRenderingContext,
+                                 InlineMinWidthData *aData) MOZ_OVERRIDE;
+  virtual void AddInlinePrefWidth(nsRenderingContext *aRenderingContext,
+                                  InlinePrefWidthData *aData) MOZ_OVERRIDE;
+  virtual nscoord GetMinWidth(nsRenderingContext *aRenderingContext) MOZ_OVERRIDE;
+  virtual nscoord GetPrefWidth(nsRenderingContext *aRenderingContext) MOZ_OVERRIDE;
+  virtual nsIAtom* GetType() const MOZ_OVERRIDE;
+  virtual nscoord GetBaseline() const MOZ_OVERRIDE;
+
+  virtual bool IsFrameOfType(uint32_t aFlags) const MOZ_OVERRIDE
+  {
+    return nsFrame::IsFrameOfType(aFlags & ~(nsIFrame::eReplaced |
+                                             nsIFrame::eLineParticipant));
+  }
+
+#ifdef ACCESSIBILITY
+  virtual mozilla::a11y::AccType AccessibleType() MOZ_OVERRIDE;
+#endif
+
+protected:
+  BRFrame(nsStyleContext* aContext) : nsFrame(aContext) {}
+  virtual ~BRFrame();
+
+  nscoord mAscent;
+};
+
+nsIFrame*
+NS_NewBRFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
+{
+  return new (aPresShell) BRFrame(aContext);
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(BRFrame)
+
+BRFrame::~BRFrame()
+{
+}
+
+nsresult
+BRFrame::Reflow(nsPresContext* aPresContext,
+                nsHTMLReflowMetrics& aMetrics,
+                const nsHTMLReflowState& aReflowState,
+                nsReflowStatus& aStatus)
+{
+  DO_GLOBAL_REFLOW_COUNT("BRFrame");
+  DISPLAY_REFLOW(aPresContext, this, aReflowState, aMetrics, aStatus);
+  aMetrics.Height() = 0; // BR frames with height 0 are ignored in quirks
+                       // mode by nsLineLayout::VerticalAlignFrames .
+                       // However, it's not always 0.  See below.
+  aMetrics.Width() = 0;
+  aMetrics.SetTopAscent(0);
+
+  // Only when the BR is operating in a line-layout situation will it
+  // behave like a BR.
+  nsLineLayout* ll = aReflowState.mLineLayout;
+  if (ll) {
+    // Note that the compatibility mode check excludes AlmostStandards
+    // mode, since this is the inline box model.  See bug 161691.
+    if ( ll->LineIsEmpty() ||
+         aPresContext->CompatibilityMode() == eCompatibility_FullStandards ) {
+      // The line is logically empty; any whitespace is trimmed away.
+      //
+      // If this frame is going to terminate the line we know
+      // that nothing else will go on the line. Therefore, in this
+      // case, we provide some height for the BR frame so that it
+      // creates some vertical whitespace.  It's necessary to use the
+      // line-height rather than the font size because the
+      // quirks-mode fix that doesn't apply the block's min
+      // line-height makes this necessary to make BR cause a line
+      // of the full line-height
+
+      // We also do this in strict mode because BR should act like a
+      // normal inline frame.  That line-height is used is important
+      // here for cases where the line-height is less than 1.
+      nsRefPtr<nsFontMetrics> fm;
+      nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fm),
+        nsLayoutUtils::FontSizeInflationFor(this));
+      aReflowState.rendContext->SetFont(fm); // FIXME: maybe not needed?
+      if (fm) {
+        nscoord logicalHeight = aReflowState.CalcLineHeight();
+        aMetrics.Height() = logicalHeight;
+        aMetrics.SetTopAscent(nsLayoutUtils::GetCenteredFontBaseline(fm, logicalHeight));
+      }
+      else {
+        aMetrics.SetTopAscent(aMetrics.Height() = 0);
+      }
+
+      // XXX temporary until I figure out a better solution; see the
+      // code in nsLineLayout::VerticalAlignFrames that zaps minY/maxY
+      // if the width is zero.
+      // XXX This also fixes bug 10036!
+      // Warning: nsTextControlFrame::CalculateSizeStandard depends on
+      // the following line, see bug 228752.
+      aMetrics.Width() = 1;
+    }
+
+    // Return our reflow status
+    uint32_t breakType = aReflowState.mStyleDisplay->mBreakType;
+    if (NS_STYLE_CLEAR_NONE == breakType) {
+      breakType = NS_STYLE_CLEAR_LINE;
+    }
+
+    aStatus = NS_INLINE_BREAK | NS_INLINE_BREAK_AFTER |
+      NS_INLINE_MAKE_BREAK_TYPE(breakType);
+    ll->SetLineEndsInBR(true);
+  }
+  else {
+    aStatus = NS_FRAME_COMPLETE;
+  }
+
+  aMetrics.SetOverflowAreasToDesiredBounds();
+
+  mAscent = aMetrics.TopAscent();
+
+  NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aMetrics);
+  return NS_OK;
+}
+
+/* virtual */ void
+BRFrame::AddInlineMinWidth(nsRenderingContext *aRenderingContext,
+                           nsIFrame::InlineMinWidthData *aData)
+{
+  aData->ForceBreak(aRenderingContext);
+}
+
+/* virtual */ void
+BRFrame::AddInlinePrefWidth(nsRenderingContext *aRenderingContext,
+                            nsIFrame::InlinePrefWidthData *aData)
+{
+  aData->ForceBreak(aRenderingContext);
+}
+
+/* virtual */ nscoord
+BRFrame::GetMinWidth(nsRenderingContext *aRenderingContext)
+{
+  nscoord result = 0;
+  DISPLAY_MIN_WIDTH(this, result);
+  return result;
+}
+
+/* virtual */ nscoord
+BRFrame::GetPrefWidth(nsRenderingContext *aRenderingContext)
+{
+  nscoord result = 0;
+  DISPLAY_PREF_WIDTH(this, result);
+  return result;
+}
+
+nsIAtom*
+BRFrame::GetType() const
+{
+  return nsGkAtoms::brFrame;
+}
+
+nscoord
+BRFrame::GetBaseline() const
+{
+  return mAscent;
+}
+
+nsIFrame::ContentOffsets BRFrame::CalcContentOffsetsFromFramePoint(nsPoint aPoint)
+{
+  ContentOffsets offsets;
+  offsets.content = mContent->GetParent();
+  if (offsets.content) {
+    offsets.offset = offsets.content->IndexOf(mContent);
+    offsets.secondaryOffset = offsets.offset;
+    offsets.associateWithNext = true;
+  }
+  return offsets;
+}
+
+nsIFrame::FrameSearchResult
+BRFrame::PeekOffsetNoAmount(bool aForward, int32_t* aOffset)
+{
+  NS_ASSERTION (aOffset && *aOffset <= 1, "aOffset out of range");
+  int32_t startOffset = *aOffset;
+  // If we hit the end of a BR going backwards, go to its beginning and stay there.
+  if (!aForward && startOffset != 0) {
+    *aOffset = 0;
+    return FOUND;
+  }
+  // Otherwise, stop if we hit the beginning, continue (forward) if we hit the end.
+  return (startOffset == 0) ? FOUND : CONTINUE;
+}
+
+nsIFrame::FrameSearchResult
+BRFrame::PeekOffsetCharacter(bool aForward, int32_t* aOffset,
+                             bool aRespectClusters)
+{
+  NS_ASSERTION (aOffset && *aOffset <= 1, "aOffset out of range");
+  // Keep going. The actual line jumping will stop us.
+  return CONTINUE;
+}
+
+nsIFrame::FrameSearchResult
+BRFrame::PeekOffsetWord(bool aForward, bool aWordSelectEatSpace, bool aIsKeyboardSelect,
+                        int32_t* aOffset, PeekWordState* aState)
+{
+  NS_ASSERTION (aOffset && *aOffset <= 1, "aOffset out of range");
+  // Keep going. The actual line jumping will stop us.
+  return CONTINUE;
+}
+
+#ifdef ACCESSIBILITY
+a11y::AccType
+BRFrame::AccessibleType()
+{
+  nsIContent *parent = mContent->GetParent();
+  if (parent && parent->IsRootOfNativeAnonymousSubtree() &&
+      parent->GetChildCount() == 1) {
+    // This <br> is the only node in a text control, therefore it is the hacky
+    // "bogus node" used when there is no text in the control
+    return a11y::eNoType;
+  }
+
+  return a11y::eHTMLBRType;
+}
+#endif
+