Oilpan: add [WillBeGarbageCollected] for Node.

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 907 matching lines @@
         if (exceptionState.hadException())
             return false;
         newContainerNode->appendChild(newChild.release(), exceptionState);
         if (exceptionState.hadException())
             return false;
     }
 
     return true;
 }
 
-PassRefPtr<Node> Document::importNode(Node* importedNode, ExceptionState& ec)
+PassRefPtrWillBeRawPtr<Node> Document::importNode(Node* importedNode, ExceptionState& ec)
 {
     UseCounter::countDeprecation(this, UseCounter::DocumentImportNodeOptionalArgument);
     return importNode(importedNode, true, ec);
 }
 
-PassRefPtr<Node> Document::importNode(Node* importedNode, bool deep, ExceptionState& exceptionState)
+PassRefPtrWillBeRawPtr<Node> Document::importNode(Node* importedNode, bool deep, ExceptionState& exceptionState)
 {
     if (!importedNode) {
         exceptionState.throwDOMException(NotSupportedError, ExceptionMessages::argumentNullOrIncorrectType(1, "Node"));
         return nullptr;
     }
 
     switch (importedNode->nodeType()) {
     case TEXT_NODE:
         return createTextNode(importedNode->nodeValue());
     case CDATA_SECTION_NODE:
@@ skipping 4793 matching lines @@
     // FIXME: Oilpan: Use a weak counted set instead.
     if (m_touchEventTargets) {
         Vector<Node*> deadNodes;
         for (TouchEventTargetSet::iterator it = m_touchEventTargets->begin(); it != m_touchEventTargets->end(); ++it) {
             if (!visitor->isAlive(it->key))
                 deadNodes.append(it->key);
         }
         for (unsigned i = 0; i < deadNodes.size(); ++i)
             didClearTouchEventHandlers(deadNodes[i]);
     }
+    if (m_domWindow && !visitor->isAlive(m_domWindow)) {
+        ASSERT(isDisposed());

[Mads Ager (chromium), 2014/05/26 06:15:20]

This seems fishy to me. If the Document is dead and the DOMWindow is still alive
they must have been explicitly disassociated. The Document must have been
detached. When a document is detached it is no longer displayed and it seems
surprising that we would need touch event handlers for something that is not
even displayed? A Document cannot be reattached. Can't we clear the touch event
handlers at that point instead of doing it via weak processing? Do we ever need
the touch event handlers after a document has been explicitly detached?

I would expect DOMWindow and Document to have strong pointers to each other as
long as they are associated. When the document is detached from a DOMWindow we
should perform cleanup. If it is never detached, the DOMWindow and the Document
should die together and no cleanup is needed? 

+        // Oilpan: this mirrors the clearing of the document object's touch
+        // handlers that happen when the DOMWindow is destructed in a non-Oilpan
+        // setting (done via DOMWindow::removeAllEventListeners().)
+        didClearTouchEventHandlers(this);
+        m_domWindow.clear();
+    }
 }
 
 void Document::trace(Visitor* visitor)
 {
     visitor->trace(m_docType);
     visitor->trace(m_implementation);
     visitor->trace(m_autofocusElement);
     visitor->trace(m_focusedElement);
     visitor->trace(m_hoverNode);
     visitor->trace(m_activeHoverElement);
@@ skipping 27 matching lines @@
     visitor->trace(m_timeline);
     visitor->trace(m_compositorPendingAnimations);
     visitor->registerWeakMembers<Document, &Document::clearWeakMembers>(this);
     DocumentSupplementable::trace(visitor);
     TreeScope::trace(visitor);
     ContainerNode::trace(visitor);
     ExecutionContext::trace(visitor);
 }
 
 } // namespace WebCore