Move Frame to the Oilpan heap.

Source/core/frame/LocalDOMWindow.cpp

Index: Source/core/frame/LocalDOMWindow.cpp
diff --git a/Source/core/frame/LocalDOMWindow.cpp b/Source/core/frame/LocalDOMWindow.cpp
index d6604f3b4211042f4662bf3159ad5b11d304fa56..0e3cbde8ba75781f02120283e85058afb02b1e91 100644
--- a/Source/core/frame/LocalDOMWindow.cpp
+++ b/Source/core/frame/LocalDOMWindow.cpp
@@ -484,7 +484,7 @@ void LocalDOMWindow::enqueuePopstateEvent(PassRefPtr<SerializedScriptValue> stat
 
 void LocalDOMWindow::statePopped(PassRefPtr<SerializedScriptValue> stateObject)
 {
-    if (!frame())
+    if (!m_frame)
         return;
 
     // Per step 11 of section 6.5.9 (history traversal) of the HTML5 spec, we
@@ -497,8 +497,6 @@ void LocalDOMWindow::statePopped(PassRefPtr<SerializedScriptValue> stateObject)
 
 LocalDOMWindow::~LocalDOMWindow()
 {
-    ASSERT(m_hasBeenReset);
-
 #if ENABLE(OILPAN)
     // Oilpan: the frame host and document objects are
     // also garbage collected; cannot notify these
@@ -508,6 +506,7 @@ LocalDOMWindow::~LocalDOMWindow()
     // Cleared when detaching document.
     ASSERT(!m_eventQueue);
 #else
+    ASSERT(m_hasBeenReset);

[Mads Ager (chromium), 2014/09/16 12:17:45]

This looks a little odd (it is not new though). We assert that the
LocalDOMWindow has been reset and then we reset it again. Isn't the reset call
redundant here?

[sof, 2014/09/17 09:42:58]

See https://codereview.chromium.org/517043003/#msg36

     reset();
 
     removeAllEventListenersInternal(DoBroadcastListenerRemoval);
@@ -542,11 +541,15 @@ Page* LocalDOMWindow::page()
     return frame() ? frame()->page() : 0;
 }
 
+#if !ENABLE(OILPAN)
 void LocalDOMWindow::frameDestroyed()
 {
     FrameDestructionObserver::frameDestroyed();
-    reset();
+    // The frame resets its LocalDOMWindow prior to frame destruction

[Mads Ager (chromium), 2014/09/16 12:17:45]

So, really, we could remove the frameDestroyed override here in the non-oilpan
build as well. But maybe the assert is worth it here? The assert is in the
destructor which is maybe enough?

[sof, 2014/09/17 09:42:58]

Hmm, it doesn't add much value -- if frame destruction should change the order
in which it issues frameDestroyed() vs clearing its LocalDOMWindow, that isn't a
problem. If it fails to do the latter, then that will cause badness regardless.

Let's remove the override; nice catch (I failed to see the potential
simplification while removing the reset() call.) I kept frameDestroyed() as a
virtual.

+    // notifications.
+    ASSERT(m_hasBeenReset);
 }
+#endif
 
 void LocalDOMWindow::willDetachFrameHost()
 {
@@ -903,7 +906,7 @@ void LocalDOMWindow::dispatchMessageEventWithOriginCheck(SecurityOrigin* intende
 
 DOMSelection* LocalDOMWindow::getSelection()
 {
-    if (!isCurrentlyDisplayedInFrame() || !m_frame)
+    if (!isCurrentlyDisplayedInFrame())
         return 0;
 
     return m_frame->document()->getSelection();
@@ -1061,8 +1064,8 @@ bool LocalDOMWindow::find(const String& string, bool caseSensitive, bool backwar
         return false;
 
     // |m_frame| can be destructed during |Editor::findString()| via
-    // |Document::updateLayou()|, e.g. event handler removes a frame.
-    RefPtr<LocalFrame> protectFrame(m_frame);
+    // |Document::updateLayout()|, e.g. event handler removes a frame.
+    RefPtrWillBeRawPtr<LocalFrame> protectFrame(m_frame.get());
 
     // FIXME (13016): Support wholeWord, searchInFrames and showDialog
     return m_frame->editor().findString(string, !backwards, caseSensitive, wrap, false);
@@ -1195,7 +1198,13 @@ int LocalDOMWindow::scrollY() const
 
 bool LocalDOMWindow::closed() const
 {
-    return !m_frame;
+    // FIXME: Oilpan: the timing of when m_frame is GCed is clearly
+    // different to what happens non-Oilpan. m_frame->hasBeenClosed()
+    // is considered in both settings to make the behavior the same --
+    // the flag is set when the WebView (and frame) is closed. Finalization
+    // of the m_frame will happen at some point later.
+    //
+    return !m_frame || m_frame->hasBeenClosed();
 }
 
 unsigned LocalDOMWindow::length() const
@@ -1864,11 +1873,10 @@ void LocalDOMWindow::showModalDialog(const String& urlString, const String& dial
 
 LocalDOMWindow* LocalDOMWindow::anonymousIndexedGetter(uint32_t index)
 {
-    LocalFrame* frame = this->frame();
-    if (!frame)
+    if (!m_frame)
         return 0;
 
-    Frame* child = frame->tree().scopedChild(index);
+    Frame* child = m_frame->tree().scopedChild(index);
     if (child)
         return child->domWindow();
 
@@ -1912,6 +1920,7 @@ void LocalDOMWindow::trace(Visitor* visitor)
     WillBeHeapSupplementable<LocalDOMWindow>::trace(visitor);
     EventTargetWithInlineData::trace(visitor);
     LifecycleContext<LocalDOMWindow>::trace(visitor);
+    FrameDestructionObserver::trace(visitor);
 }
 
 v8::Handle<v8::Object> LocalDOMWindow::wrap(v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)