Move Frame to the Oilpan heap.

Source/core/page/FrameTree.h

Index: Source/core/page/FrameTree.h
diff --git a/Source/core/page/FrameTree.h b/Source/core/page/FrameTree.h
index e2f8fcdf392e34bd3da6ca845f3e33e246ad323f..4213ea9679f17a8ab4bfad50ea31e7dd9094744b 100644
--- a/Source/core/page/FrameTree.h
+++ b/Source/core/page/FrameTree.h
@@ -20,6 +20,7 @@
 #ifndef FrameTree_h
 #define FrameTree_h
 
+#include "platform/heap/Handle.h"
 #include "wtf/text/AtomicString.h"
 
 namespace blink {
@@ -27,8 +28,9 @@ namespace blink {
 class Frame;
 class TreeScope;
 
-class FrameTree {
+class FrameTree FINAL {
     WTF_MAKE_NONCOPYABLE(FrameTree);
+    ALLOW_ONLY_INLINE_ALLOCATION();
 public:
     explicit FrameTree(Frame* thisFrame);
     ~FrameTree();
@@ -60,13 +62,15 @@ public:
     unsigned scopedChildCount() const;
     void invalidateScopedChildCount();
 
+    void trace(Visitor*);
+
 private:
     Frame* deepLastChild() const;
     AtomicString uniqueChildName(const AtomicString& requestedName) const;
     bool uniqueNameExists(const AtomicString& name) const;
     unsigned scopedChildCount(TreeScope*) const;
 
-    Frame* m_thisFrame;
+    RawPtrWillBeMember<Frame> m_thisFrame;
 
     AtomicString m_name; // The actual frame name (may be empty).
     AtomicString m_uniqueName;