Move Frame to the Oilpan heap.

Source/web/WebFrame.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "public/web/WebFrame.h"
 
 #include "core/frame/RemoteFrame.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "platform/UserGestureIndicator.h"
+#include "platform/heap/Handle.h"
 #include "web/OpenedFrameTracker.h"
 #include "web/WebLocalFrameImpl.h"
 #include "web/WebRemoteFrameImpl.h"
 #include <algorithm>
 
 namespace blink {
 
 Frame* toCoreFrame(const WebFrame* frame)
 {
     if (!frame)
         return 0;
 
     return frame->isWebLocalFrame()
         ? static_cast<Frame*>(toWebLocalFrameImpl(frame)->frame())
         : toWebRemoteFrameImpl(frame)->frame();
 }
 
 bool WebFrame::swap(WebFrame* frame)
 {
     using std::swap;
-    RefPtr<Frame> oldFrame = toCoreFrame(this);
+    RefPtrWillBeRawPtr<Frame> oldFrame = toCoreFrame(this);
 
     // All child frames must be detached first.
     oldFrame->detachChildren();
 
     // If the frame has been detached during detaching its children, return
     // immediately.
     // FIXME: There is no unit test for this condition, so one needs to be
     // written.
     if (!oldFrame->host())
         return false;
@@ skipping 181 matching lines @@
     , m_opener(0)
     , m_openedFrameTracker(new OpenedFrameTracker)
 {
 }
 
 WebFrame::~WebFrame()
 {
     m_openedFrameTracker.reset(0);
 }
 
+void WebFrame::traceChildren(Visitor* visitor, WebFrame* frame)

[Mads Ager (chromium), 2014/09/18 12:00:59]

It is probably a good idea to continue to trace the children this way to be
completely safe. With the self-persistents it is probably not strictly
necessary, but with conservative stack scanning in the picture it is nice to be
sure that all the children are kept alive if we find one of the nodes.

[sof, 2014/09/18 13:31:15]

Very good point, I hadn't realized the implication here of that self-sustaining
change. Hmm, fine either way, but tracing errs on the side of caution, so let's
keep it.

+{
+#if ENABLE(OILPAN)
+    // Trace the children frames.
+    WebFrame* child = frame ? frame->firstChild() : 0;
+    while (child) {
+        if (child->isWebLocalFrame())
+            visitor->trace(toWebLocalFrameImpl(child));
+        else
+            visitor->trace(toWebRemoteFrameImpl(child));
+
+        child = child->nextSibling();
+    }
+#endif
+}
+
 } // namespace blink