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"
@@ skipping 202 matching lines @@
     , m_opener(0)
     , m_openedFrameTracker(new OpenedFrameTracker)
 {
 }
 
 WebFrame::~WebFrame()
 {
     m_openedFrameTracker.reset(0);
 }
 
+void WebFrame::trace(Visitor* visitor, WebFrame* frame)

[haraken, 2014/09/08 07:25:59]

It looks dangerous to do something non-trivial in trace methods (although I
haven't checked if this particular trace method is safe or not), because trace
methods can be called while constructing an object.

Can we restructure the code so that trace methods just call
visitor->trace(m_member)'s?

[sof, 2014/09/08 21:17:46]

Perhaps the (static) method should be renamed as traceChildren()? This is
tracing the children of a WebFrame, allowing that tracing code to be shared
between local and remote "impl" objects.

+{
+#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