Return references to IntRects to save space in CompositingRequirementsUpdater.

third_party/WebKit/Source/core/paint/PaintLayer.h

Index: third_party/WebKit/Source/core/paint/PaintLayer.h
diff --git a/third_party/WebKit/Source/core/paint/PaintLayer.h b/third_party/WebKit/Source/core/paint/PaintLayer.h
index e94c22d92b6cd1759a52c6207fdd56e3ddd939eb..03b5771d601876696537c989339b283c79e98c96 100644
--- a/third_party/WebKit/Source/core/paint/PaintLayer.h
+++ b/third_party/WebKit/Source/core/paint/PaintLayer.h
@@ -717,11 +717,11 @@ class CORE_EXPORT PaintLayer : public DisplayItemClient {
       bool hasRootScrollerAsDescendant);
   void didUpdateCompositingInputs();
 
-  IntRect clippedAbsoluteBoundingBox() const {
+  const IntRect& clippedAbsoluteBoundingBox() const {
     DCHECK(!m_needsAncestorDependentCompositingInputsUpdate);
     return m_ancestorDependentCompositingInputs.clippedAbsoluteBoundingBox;
   }
-  IntRect unclippedAbsoluteBoundingBox() const {
+  const IntRect& unclippedAbsoluteBoundingBox() const {
     DCHECK(!m_needsAncestorDependentCompositingInputsUpdate);
     return m_ancestorDependentCompositingInputs.unclippedAbsoluteBoundingBox;
   }