Move the Widget hierarchy to the Oilpan heap.

Source/core/frame/LocalFrame.h

Index: Source/core/frame/LocalFrame.h
diff --git a/Source/core/frame/LocalFrame.h b/Source/core/frame/LocalFrame.h
index 46e38899fc12273a06901b872e892e86aab6a133..f345a2a28645e5395f293051126f5a25e5dceb6d 100644
--- a/Source/core/frame/LocalFrame.h
+++ b/Source/core/frame/LocalFrame.h
@@ -70,7 +70,7 @@ namespace blink {
         virtual bool isLocalFrame() const OVERRIDE { return true; }
 
         void init();
-        void setView(PassRefPtr<FrameView>);
+        void setView(PassRefPtrWillBeRawPtr<FrameView>);
         void createView(const IntSize&, const Color&, bool,
             ScrollbarMode = ScrollbarAuto, bool horizontalLock = false,
             ScrollbarMode = ScrollbarAuto, bool verticalLock = false);
@@ -169,7 +169,7 @@ namespace blink {
         mutable FrameLoader m_loader;
         mutable NavigationScheduler m_navigationScheduler;
 
-        RefPtr<FrameView> m_view;
+        RefPtrWillBeMember<FrameView> m_view;
         // Usually 0. Non-null if this is the top frame of PagePopup.
         RefPtrWillBeMember<Element> m_pagePopupOwner;