Reuse cc::PictureLayers when possible for SPv2.

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1064 matching lines @@
 
 String LayoutObject::debugName() const
 {
     StringBuilder name;
     name.append(decoratedName());
 
     if (const Node* node = this->node()) {
         name.append(' ');
         name.append(node->debugName());
     }
+    name.append(String::format(" %p", this));

[Xianzhu, 2016/09/20 23:13:41]

The output of debugName() is used in layout test outputs, so it should not
include anything that can change between runs.  

[chrishtr, 2016/09/20 23:43:59]

Good point. Removed.

     return name.toString();
 }
 
 LayoutRect LayoutObject::visualRect() const
 {
     return previousPaintInvalidationRect();
 }
 
 bool LayoutObject::isPaintInvalidationContainer() const
 {
@@ skipping 2190 matching lines @@
         const blink::LayoutObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
     } else {
         WTFLogAlways("%s", "Cannot showLayoutTree. Root is (nil)");
     }
 }
 
 #endif