Bug 539356 - Part 9 - Implement DLBI. r=roc,bz,jwatt

layout/forms/nsButtonFrameRenderer.cpp

@@ -117,11 +117,18 @@ public:
   }
   virtual void Paint(nsDisplayListBuilder* aBuilder,
                      nsRenderingContext* aCtx);
+  virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder, bool* aSnap);
   NS_DISPLAY_DECL_NAME("ButtonBorderBackground", TYPE_BUTTON_BORDER_BACKGROUND)
 private:
   nsButtonFrameRenderer* mBFR;
 };
 
+nsRect
+nsDisplayButtonBorderBackground::GetBounds(nsDisplayListBuilder* aBuilder, bool* aSnap) {
+  *aSnap = false;
+  return mFrame->GetVisualOverflowRectRelativeToSelf() + ToReferenceFrame();
+}
+
 class nsDisplayButtonForeground : public nsDisplayItem {
 public:
   nsDisplayButtonForeground(nsDisplayListBuilder* aBuilder,