Update PaintLayer size during layout, not after.

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

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
@@ skipping 269 matching lines @@
 
   bool IsRootLayer() const { return is_root_layer_; }
 
   PaintLayerCompositor* Compositor() const;
 
   // Notification from the layoutObject that its content changed (e.g. current
   // frame of image changed).  Allows updates of layer content without
   // invalidating paint.
   void ContentChanged(ContentChangeType);
 
-  void UpdateScrollingAfterLayout();
+  void UpdateSizeAndScrollingAfterLayout();
 
   void UpdateLayerPosition();
   void UpdateLayerPositionsAfterLayout();
   void UpdateLayerPositionsAfterOverflowScroll();
 
   PaintLayer* EnclosingPaginationLayer() const {
     return rare_data_ ? rare_data_->enclosing_pagination_layer : nullptr;
   }
 
   void UpdateTransformationMatrix();
@@ skipping 976 matching lines @@
 
 }  // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 CORE_EXPORT void showLayerTree(const blink::PaintLayer*);
 CORE_EXPORT void showLayerTree(const blink::LayoutObject*);
 #endif
 
 #endif  // Layer_h