Update PaintLayer size during layout, not after.

third_party/WebKit/Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 733 matching lines @@
 FloatRect LayoutBox::LocalBoundingBoxRectForAccessibility() const {
   return FloatRect(0, 0, frame_rect_.Width().ToFloat(),
                    frame_rect_.Height().ToFloat());
 }
 
 void LayoutBox::UpdateAfterLayout() {
   // Transform-origin depends on box size, so we need to update the layer
   // transform after layout.
   if (HasLayer()) {
     Layer()->UpdateTransformationMatrix();
-    Layer()->UpdateScrollingAfterLayout();
+    Layer()->UpdateSizeAndScrollingAfterLayout();
   }
 }
 
 LayoutUnit LayoutBox::LogicalHeightWithVisibleOverflow() const {
   if (!overflow_ || HasOverflowClip())
     return LogicalHeight();
   LayoutRect overflow = LayoutOverflowRect();
   if (Style()->IsHorizontalWritingMode())
     return overflow.MaxY();
   return overflow.MaxX();
@@ skipping 69 matching lines @@
 }
 
 void LayoutBox::SetLocationAndUpdateOverflowControlsIfNeeded(
     const LayoutPoint& location) {
   if (HasOverflowClip()) {
     IntSize old_pixel_snapped_border_rect_size =
         PixelSnappedBorderBoxRect().Size();
     SetLocation(location);
     if (PixelSnappedBorderBoxRect().Size() !=
         old_pixel_snapped_border_rect_size) {
-      Layer()->UpdateScrollingAfterLayout();
+      Layer()->UpdateSizeAndScrollingAfterLayout();
     }
     return;
   }
 
   SetLocation(location);
 }
 
 IntRect LayoutBox::AbsoluteContentBox() const {
   // This is wrong with transforms and flipped writing modes.
   IntRect rect = PixelSnappedIntRect(ContentBoxRect());
@@ skipping 5052 matching lines @@
 void LayoutBox::MutableForPainting::
     SavePreviousContentBoxSizeAndLayoutOverflowRect() {
   auto& rare_data = GetLayoutBox().EnsureRareData();
   rare_data.has_previous_content_box_size_and_layout_overflow_rect_ = true;
   rare_data.previous_content_box_size_ = GetLayoutBox().ContentBoxRect().Size();
   rare_data.previous_layout_overflow_rect_ =
       GetLayoutBox().LayoutOverflowRect();
 }
 
 }  // namespace blink