--- a/layout/generic/nsFrame.cpp
+++ b/layout/generic/nsFrame.cpp
@@ -1272,34 +1272,35 @@ nsIFrame::OutsetBorderRadii(nscoord aRad
     if (aRadii[hc1] > 0)
       aRadii[hc1] += offset;
     if (aRadii[hc2] > 0)
       aRadii[hc2] += offset;
   }
 }
 
 /* virtual */ bool
-nsIFrame::GetBorderRadii(nscoord aRadii[8]) const
+nsIFrame::GetBorderRadii(const nsSize& aFrameSize, const nsSize& aBorderArea,
+                         int aSkipSides, nscoord aRadii[8]) const
 {
   if (IsThemed()) {
     // When we're themed, the native theme code draws the border and
     // background, and therefore it doesn't make sense to tell other
     // code that's interested in border-radius that we have any radii.
     //
     // In an ideal world, we might have a way for the them to tell us an
     // border radius, but since we don't, we're better off assuming
     // zero.
     NS_FOR_CSS_HALF_CORNERS(corner) {
       aRadii[corner] = 0;
     }
     return false;
   }
-  nsSize size = GetSize();
-  return ComputeBorderRadii(StyleBorder()->mBorderRadius, size, size,
-                            GetSkipSides(), aRadii);
+  return ComputeBorderRadii(StyleBorder()->mBorderRadius,
+                            aFrameSize, aBorderArea,
+                            aSkipSides, aRadii);
 }
 
 bool
 nsIFrame::GetPaddingBoxBorderRadii(nscoord aRadii[8]) const
 {
   if (!GetBorderRadii(aRadii))
     return false;
   InsetBorderRadii(aRadii, GetUsedBorder());

--- a/layout/generic/nsGfxScrollFrame.cpp
+++ b/layout/generic/nsGfxScrollFrame.cpp
@@ -4361,20 +4361,25 @@ ReduceRadii(nscoord aXBorder, nscoord aY
  * Implement an override for nsIFrame::GetBorderRadii to ensure that
  * the clipping region for the border radius does not clip the scrollbars.
  *
  * In other words, we require that the border radius be reduced until the
  * inner border radius at the inner edge of the border is 0 wherever we
  * have scrollbars.
  */
 bool
-ScrollFrameHelper::GetBorderRadii(nscoord aRadii[8]) const
+ScrollFrameHelper::GetBorderRadii(const nsSize& aFrameSize,
+                                  const nsSize& aBorderArea,
+                                  int aSkipSides,
+                                  nscoord aRadii[8]) const
 {
-  if (!mOuter->nsContainerFrame::GetBorderRadii(aRadii))
+  if (!mOuter->nsContainerFrame::GetBorderRadii(aFrameSize, aBorderArea,
+                                                aSkipSides, aRadii)) {
     return false;
+  }
 
   // Since we can use GetActualScrollbarSizes (rather than
   // GetDesiredScrollbarSizes) since this doesn't affect reflow, we
   // probably should.
   nsMargin sb = GetActualScrollbarSizes();
   nsMargin border = mOuter->GetUsedBorder();
 
   if (sb.left > 0 || sb.top > 0) {

--- a/layout/generic/nsGfxScrollFrame.h
+++ b/layout/generic/nsGfxScrollFrame.h
@@ -66,17 +66,18 @@ public:
                         const nsDisplayListSet& aLists);
 
   void AppendScrollPartsTo(nsDisplayListBuilder*   aBuilder,
                            const nsRect&           aDirtyRect,
                            const nsDisplayListSet& aLists,
                            bool&                   aCreateLayer,
                            bool                    aPositioned);
 
-  bool GetBorderRadii(nscoord aRadii[8]) const;
+  bool GetBorderRadii(const nsSize& aFrameSize, const nsSize& aBorderArea,
+                      int aSkipSides, nscoord aRadii[8]) const;
 
   // nsIReflowCallback
   virtual bool ReflowFinished() MOZ_OVERRIDE;
   virtual void ReflowCallbackCanceled() MOZ_OVERRIDE;
 
   /**
    * @note This method might destroy the frame, pres shell and other objects.
    * Called when the 'curpos' attribute on one of the scrollbars changes.
@@ -466,18 +467,19 @@ public:
                                nsHTMLReflowMetrics* aMetrics,
                                bool aFirstPass);
   nsresult ReflowContents(ScrollReflowState* aState,
                           const nsHTMLReflowMetrics& aDesiredSize);
   void PlaceScrollArea(const ScrollReflowState& aState,
                        const nsPoint& aScrollPosition);
   nscoord GetIntrinsicVScrollbarWidth(nsRenderingContext *aRenderingContext);
 
-  virtual bool GetBorderRadii(nscoord aRadii[8]) const MOZ_OVERRIDE {
-    return mHelper.GetBorderRadii(aRadii);
+  virtual bool GetBorderRadii(const nsSize& aFrameSize, const nsSize& aBorderArea,
+                              int aSkipSides, nscoord aRadii[8]) const MOZ_OVERRIDE {
+    return mHelper.GetBorderRadii(aFrameSize, aBorderArea, aSkipSides, aRadii);
   }
 
   virtual nscoord GetMinWidth(nsRenderingContext *aRenderingContext) MOZ_OVERRIDE;
   virtual nscoord GetPrefWidth(nsRenderingContext *aRenderingContext) MOZ_OVERRIDE;
   virtual nsresult GetPadding(nsMargin& aPadding) MOZ_OVERRIDE;
   virtual bool IsCollapsed() MOZ_OVERRIDE;
   
   virtual nsresult Reflow(nsPresContext*           aPresContext,
@@ -803,18 +805,19 @@ public:
   virtual nsSize GetMinSize(nsBoxLayoutState& aBoxLayoutState) MOZ_OVERRIDE;
   virtual nsSize GetPrefSize(nsBoxLayoutState& aBoxLayoutState) MOZ_OVERRIDE;
   virtual nsSize GetMaxSize(nsBoxLayoutState& aBoxLayoutState) MOZ_OVERRIDE;
   virtual nscoord GetBoxAscent(nsBoxLayoutState& aBoxLayoutState) MOZ_OVERRIDE;
 
   NS_IMETHOD DoLayout(nsBoxLayoutState& aBoxLayoutState) MOZ_OVERRIDE;
   virtual nsresult GetPadding(nsMargin& aPadding) MOZ_OVERRIDE;
 
-  virtual bool GetBorderRadii(nscoord aRadii[8]) const MOZ_OVERRIDE {
-    return mHelper.GetBorderRadii(aRadii);
+  virtual bool GetBorderRadii(const nsSize& aFrameSize, const nsSize& aBorderArea,
+                              int aSkipSides, nscoord aRadii[8]) const MOZ_OVERRIDE {
+    return mHelper.GetBorderRadii(aFrameSize, aBorderArea, aSkipSides, aRadii);
   }
 
   nsresult Layout(nsBoxLayoutState& aState);
   void LayoutScrollArea(nsBoxLayoutState& aState, const nsPoint& aScrollPosition);
 
   static bool AddRemoveScrollbar(bool& aHasScrollbar, 
                                    nscoord& aXY, 
                                    nscoord& aSize, 

--- a/layout/generic/nsIFrame.h
+++ b/layout/generic/nsIFrame.h
@@ -1037,22 +1037,29 @@ public:
    * radii into zero, and OutsetBorderRadii does not inflate zero radii.
    * Therefore, callers should always inset or outset directly from the
    * original value coming from style.
    */
   static void InsetBorderRadii(nscoord aRadii[8], const nsMargin &aOffsets);
   static void OutsetBorderRadii(nscoord aRadii[8], const nsMargin &aOffsets);
 
   /**
-   * Fill in border radii for this frame.  Return whether any are
-   * nonzero.
-   *
+   * Fill in border radii for this frame.  Return whether any are nonzero.
    * Indices into aRadii are the NS_CORNER_* constants in nsStyleConsts.h
+   * aSkipSides is a union of SIDE_BIT_LEFT/RIGHT/TOP/BOTTOM bits that says
+   * which side(s) to skip.
    */
-  virtual bool GetBorderRadii(nscoord aRadii[8]) const;
+  virtual bool GetBorderRadii(const nsSize& aFrameSize,
+                              const nsSize& aBorderArea,
+                              int aSkipSides,
+                              nscoord aRadii[8]) const;
+  bool GetBorderRadii(nscoord aRadii[8]) const {
+    nsSize sz = GetSize();
+    return GetBorderRadii(sz, sz, GetSkipSides(), aRadii);
+  }
 
   bool GetPaddingBoxBorderRadii(nscoord aRadii[8]) const;
   bool GetContentBoxBorderRadii(nscoord aRadii[8]) const;
 
   /**
    * Get the position of the frame's baseline, relative to the top of
    * the frame (its top border edge).  Only valid when Reflow is not
    * needed.

--- a/layout/tables/nsTableCellFrame.cpp
+++ b/layout/tables/nsTableCellFrame.cpp
@@ -1098,17 +1098,20 @@ nsBCTableCellFrame::GetType() const
 nsBCTableCellFrame::GetUsedBorder() const
 {
   nsMargin result;
   GetBorderWidth(result);
   return result;
 }
 
 /* virtual */ bool
-nsBCTableCellFrame::GetBorderRadii(nscoord aRadii[8]) const
+nsBCTableCellFrame::GetBorderRadii(const nsSize& aFrameSize,
+                                   const nsSize& aBorderArea,
+                                   int aSkipSides,
+                                   nscoord aRadii[8]) const
 {
   NS_FOR_CSS_HALF_CORNERS(corner) {
     aRadii[corner] = 0;
   }
   return false;
 }
 
 #ifdef DEBUG_FRAME_DUMP

--- a/layout/tables/nsTableCellFrame.h
+++ b/layout/tables/nsTableCellFrame.h
@@ -293,17 +293,20 @@ public:
 
   nsBCTableCellFrame(nsStyleContext* aContext);
 
   ~nsBCTableCellFrame();
 
   virtual nsIAtom* GetType() const MOZ_OVERRIDE;
 
   virtual nsMargin GetUsedBorder() const MOZ_OVERRIDE;
-  virtual bool GetBorderRadii(nscoord aRadii[8]) const MOZ_OVERRIDE;
+  virtual bool GetBorderRadii(const nsSize& aFrameSize,
+                              const nsSize& aBorderArea,
+                              int aSkipSides,
+                              nscoord aRadii[8]) const MOZ_OVERRIDE;
 
   // Get the *inner half of the border only*, in twips.
   virtual nsMargin* GetBorderWidth(nsMargin& aBorder) const MOZ_OVERRIDE;
 
   // Get the *inner half of the border only*, in pixels.
   BCPixelSize GetBorderWidth(mozilla::css::Side aSide) const;
 
   // Set the full (both halves) width of the border