[S.P.] Don't draw frames of animated images that are offscreen

Source/core/layout/LayoutObject.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 232 matching lines @@
 #ifndef NDEBUG
         if (paintInvalidationStateIsDirty()) {
             showLayoutTreeForThis();
             ASSERT_NOT_REACHED();
         }
 #endif
     }
 
     void assertSubtreeClearedPaintInvalidationState() const
     {
+        if (RuntimeEnabledFeatures::slimmingPaintEnabled())

[esprehn, 2015/03/25 05:06:36]

This means bugs can sneak in, if you use a separate vector you can leave the
assert which is good.

+            return;
         for (const LayoutObject* renderer = this; renderer; renderer = renderer->nextInPreOrder())
             renderer->assertRendererClearedPaintInvalidationState();
     }
 
 #endif
 
     // FIXME: This could be used when changing the size of a renderer without children to skip some invalidations.
     // FIXME: This is incorrect for document element. Remove this when we enable slimming paint.
     bool rendererHasNoBoxEffectObsolete() const
     {
@@ skipping 1398 matching lines @@
 void showTree(const blink::LayoutObject*);
 void showLineTree(const blink::LayoutObject*);
 void showLayoutTree(const blink::LayoutObject* object1);
 // We don't make object2 an optional parameter so that showLayoutTree
 // can be called from gdb easily.
 void showLayoutTree(const blink::LayoutObject* object1, const blink::LayoutObject* object2);
 
 #endif
 
 #endif // LayoutObject_h