Merge 142760

Source/WebCore/rendering/RenderLayerModelObject.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 Apple Inc. All rights reserved.
  * Copyright (C) 2010, 2012 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 58 matching lines @@
     m_layer->insertOnlyThisLayer();
 }
 
 bool RenderLayerModelObject::hasSelfPaintingLayer() const
 {
     return m_layer && m_layer->isSelfPaintingLayer();
 }
 
 void RenderLayerModelObject::willBeDestroyed()
 {
+    if (isPositioned()) {
+        // Don't use this->view() because the document's renderView has been set to 0 during destruction.
+        if (Frame* frame = this->frame()) {
+            if (FrameView* frameView = frame->view()) {
+                if (style()->hasViewportConstrainedPosition())
+                    frameView->removeViewportConstrainedObject(this);
+            }
+        }
+    }
+
     // RenderObject::willBeDestroyed calls back to destroyLayer() for layer destruction
     RenderObject::willBeDestroyed();
 }
 
 void RenderLayerModelObject::styleWillChange(StyleDifference diff, const RenderStyle* newStyle)
 {
     s_wasFloating = isFloating();
     s_hadLayer = hasLayer();
     s_hadTransform = hasTransform();
     if (s_hadLayer)
@@ skipping 88 matching lines @@
 
 void RenderLayerModelObject::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
 {
     MemoryClassInfo info(memoryObjectInfo, this, PlatformMemoryTypes::Rendering);
     RenderObject::reportMemoryUsage(memoryObjectInfo);
     info.addWeakPointer(m_layer);
 }
 
 } // namespace WebCore