Oilpan: Prepare to move AXObjectCache to the heap

Source/modules/accessibility/AXObjectCacheImpl.cpp

Index: Source/modules/accessibility/AXObjectCacheImpl.cpp
diff --git a/Source/modules/accessibility/AXObjectCacheImpl.cpp b/Source/modules/accessibility/AXObjectCacheImpl.cpp
index c7865471bdf926a65fff9e9bb2ca35dd76675bff..c45280df2ac8e647830d83d0eac959cff9d89a8d 100644
--- a/Source/modules/accessibility/AXObjectCacheImpl.cpp
+++ b/Source/modules/accessibility/AXObjectCacheImpl.cpp
@@ -85,20 +85,28 @@ namespace blink {
 using namespace HTMLNames;
 
 // static
-PassOwnPtr<AXObjectCache> AXObjectCacheImpl::create(Document& document)
+PassOwnPtrWillBeRawPtr<AXObjectCache> AXObjectCacheImpl::create(Document& document)
 {
-    return adoptPtr(new AXObjectCacheImpl(document));
+    return adoptPtrWillBeNoop(new AXObjectCacheImpl(document));
 }
 
 AXObjectCacheImpl::AXObjectCacheImpl(Document& document)
     : m_document(document)
     , m_modificationCount(0)
+#if ENABLE(ASSERT)
+    , m_hasBeenDisposed(false)
+#endif
     , m_notificationPostTimer(this, &AXObjectCacheImpl::notificationPostTimerFired)
 {
 }
 
 AXObjectCacheImpl::~AXObjectCacheImpl()
 {
+    ASSERT(m_hasBeenDisposed);
+}
+
+void AXObjectCacheImpl::dispose()
+{
     m_notificationPostTimer.stop();
 
     HashMap<AXID, RefPtr<AXObject>>::iterator end = m_objects.end();
@@ -107,6 +115,10 @@ AXObjectCacheImpl::~AXObjectCacheImpl()
         obj->detach();
         removeAXID(obj);
     }
+
+#if ENABLE(ASSERT)
+    m_hasBeenDisposed = true;
+#endif
 }
 
 AXObject* AXObjectCacheImpl::root()
@@ -1347,4 +1359,10 @@ void AXObjectCacheImpl::setCanvasObjectBounds(Element* element, const LayoutRect
     obj->setElementRect(rect);
 }
 
+DEFINE_TRACE(AXObjectCacheImpl)
+{
+    AXObjectCache::trace(visitor);

[haraken, 2015/05/29 09:16:19]

Make this a tail call.

[keishi, 2015/06/08 06:27:52]

Done.

+    visitor->template registerWeakMembers<AXObjectCacheImpl, &AXObjectCacheImpl::clearWeakMembers>(this);
+}
+
 } // namespace blink