Oilpan: Remove guardRef and guardDeref from TreeScope.

Source/core/dom/shadow/ShadowRoot.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 50 matching lines @@
     , m_descendantInsertionPointsIsValid(false)
 {
     ScriptWrappable::init(this);
 }
 
 ShadowRoot::~ShadowRoot()
 {
     ASSERT(!m_prev);
     ASSERT(!m_next);
 
+#if !ENABLE(OILPAN)
     if (m_shadowRootRareData && m_shadowRootRareData->styleSheets())
         m_shadowRootRareData->styleSheets()->detachFromDocument();
 
     document().styleEngine()->didRemoveShadowRoot(this);

[haraken, 2014/04/25 14:30:32]

I wonder why these lines are not written in ShadowRoot::removedFrom(). Probably
do we need to add these lines in ShadowRoot::removedFrom() for #if
ENABLE(OILPAN)?

A better approach would be to just move these lines to
ShadowRoot::removedFrom(). Then we don't need to use #if.

[Mads Ager (chromium), 2014/04/28 09:45:21]

No, we shouldn't have this in removedFrom. We should never call any of these
with Oilpan. The style sheet list and the document now live and die together
(strong pointers in both directions) and the shadow root collection in the style
engine is weak so that part is taken care of with weak processing.

+#endif
 
     // We cannot let ContainerNode destructor call willBeDeletedFromDocument()
     // for this ShadowRoot instance because TreeScope destructor
     // clears Node::m_treeScope thus ContainerNode is no longer able
     // to access it Document reference after that.
     willBeDeletedFromDocument();
 
     // We must remove all of our children first before the TreeScope destructor
     // runs so we don't go through TreeScopeAdopter for each child with a
     // destructed tree scope in each descendant.
@@ skipping 138 matching lines @@
     ASSERT(hasScopedHTMLStyleChild() && m_numberOfStyles > 0);
     --m_numberOfStyles;
     setHasScopedHTMLStyleChild(m_numberOfStyles > 0);
 }
 
 ShadowRootRareData* ShadowRoot::ensureShadowRootRareData()
 {
     if (m_shadowRootRareData)
         return m_shadowRootRareData.get();
 
-    m_shadowRootRareData = adoptPtr(new ShadowRootRareData);
+    m_shadowRootRareData = adoptPtrWillBeNoop(new ShadowRootRareData);
     return m_shadowRootRareData.get();
 }
 
 bool ShadowRoot::containsShadowElements() const
 {
     return m_shadowRootRareData ? m_shadowRootRareData->containsShadowElements() : 0;
 }
 
 bool ShadowRoot::containsContentElements() const
 {
@@ skipping 82 matching lines @@
 }
 
 StyleSheetList* ShadowRoot::styleSheets()
 {
     if (!ensureShadowRootRareData()->styleSheets())
         m_shadowRootRareData->setStyleSheets(StyleSheetList::create(this));
 
     return m_shadowRootRareData->styleSheets();
 }
 
+void ShadowRoot::trace(Visitor* visitor)
+{
+    visitor->trace(m_shadowRootRareData);
+    TreeScope::trace(visitor);
+    DocumentFragment::trace(visitor);
 }
+
+}