Move the Widget hierarchy to the Oilpan heap.

Source/web/PageWidgetDelegate.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 31 matching lines @@
 #include "platform/graphics/GraphicsContext.h"
 #include "public/web/WebInputEvent.h"
 #include "web/PageOverlayList.h"
 #include "web/WebInputEventConversion.h"
 #include "wtf/CurrentTime.h"
 
 namespace blink {
 
 void PageWidgetDelegate::animate(Page& page, double monotonicFrameBeginTime, LocalFrame& root)
 {
-    RefPtr<FrameView> view = root.view();
+    RefPtrWillBeRawPtr<FrameView> view = root.view();
     if (!view)
         return;
     page.autoscrollController().animate(monotonicFrameBeginTime);
     page.animator().serviceScriptedAnimations(monotonicFrameBeginTime);
 }
 
 void PageWidgetDelegate::layout(Page& page, LocalFrame& root)
 {
     page.animator().updateLayoutAndStyleForPainting(&root);
 }
@@ skipping 127 matching lines @@
 {
     return mainFrame.eventHandler().handleWheelEvent(PlatformWheelEventBuilder(mainFrame.view(), event));
 }
 
 bool PageWidgetEventHandler::handleTouchEvent(LocalFrame& mainFrame, const WebTouchEvent& event)
 {
     return mainFrame.eventHandler().handleTouchEvent(PlatformTouchEventBuilder(mainFrame.view(), event));
 }
 
 } // namespace blink