Don't call DirtyStackingContextZOrderLists during document shutdown

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

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. 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 1285 matching lines @@
   if (old_child->PreviousSibling())
     old_child->PreviousSibling()->SetNextSibling(old_child->NextSibling());
   if (old_child->NextSibling())
     old_child->NextSibling()->SetPreviousSibling(old_child->PreviousSibling());
 
   if (first_ == old_child)
     first_ = old_child->NextSibling();
   if (last_ == old_child)
     last_ = old_child->PreviousSibling();
 
-  if (Compositor()) {
-    if (!old_child->StackingNode()->IsStacked() &&
-        !GetLayoutObject().DocumentBeingDestroyed())
-      Compositor()->SetNeedsCompositingUpdate(kCompositingUpdateRebuildTree);
-  }
+  if (!GetLayoutObject().DocumentBeingDestroyed()) {
+    if (Compositor()) {
+      if (!old_child->StackingNode()->IsStacked())
+        Compositor()->SetNeedsCompositingUpdate(kCompositingUpdateRebuildTree);
+    }
 
-  if (old_child->StackingNode()->IsStacked() || old_child->FirstChild()) {
-    // Dirty the z-order list in which we are contained.  When called via the
-    // reattachment process in removeOnlyThisLayer, the layer may already be
-    // disconnected from the main layer tree, so we need to null-check the
-    // |stackingContext| value.
-    old_child->StackingNode()->DirtyStackingContextZOrderLists();
+    if (old_child->StackingNode()->IsStacked() || old_child->FirstChild()) {
+      // Dirty the z-order list in which we are contained.  When called via the
+      // reattachment process in removeOnlyThisLayer, the layer may already be
+      // disconnected from the main layer tree, so we need to null-check the
+      // |stackingContext| value.
+      old_child->StackingNode()->DirtyStackingContextZOrderLists();
+    }
   }
 
   if (GetLayoutObject().Style()->Visibility() != EVisibility::kVisible)
     DirtyVisibleContentStatus();
 
   old_child->SetPreviousSibling(0);
   old_child->SetNextSibling(0);
   old_child->parent_ = 0;
 
   // Remove any ancestor overflow layers which descended into the removed child.
@@ skipping 1988 matching lines @@
 }
 
 void showLayerTree(const blink::LayoutObject* layoutObject) {
   if (!layoutObject) {
     LOG(INFO) << "Cannot showLayerTree. Root is (nil)";
     return;
   }
   showLayerTree(layoutObject->EnclosingLayer());
 }
 #endif