[Oilpan] Fix wrong usage off heap collections in WebDevToolsAgentImpl

third_party/WebKit/Source/web/WebFrameWidgetImpl.h

 /*
  * Copyright (C) 2014 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 39 matching lines @@
 class Element;
 class LocalFrame;
 class Page;
 class PaintLayerCompositor;
 class UserGestureToken;
 class WebCompositorAnimationTimeline;
 class WebLayer;
 class WebLayerTreeView;
 class WebMouseEvent;
 class WebMouseWheelEvent;
+class WebFrameWidgetImpl;
+
+using WebFrameWidgetsSet = WillBePersistentHeapHashSet<RawPtrWillBeWeakMember<WebFrameWidgetImpl>>;
 
 class WebFrameWidgetImpl final : public RefCountedWillBeGarbageCollectedFinalized<WebFrameWidgetImpl>
     , public WebFrameWidget
     , public PageWidgetEventHandler {
 public:
     static WebFrameWidgetImpl* create(WebWidgetClient*, WebLocalFrame*);
-    static HashSet<WebFrameWidgetImpl*>& allInstances();
+    static WebFrameWidgetsSet& allInstances();
 
     // WebWidget functions:
     void close() override;
     WebSize size() override;
     void willStartLiveResize() override;
     void resize(const WebSize&) override;
     void resizeVisualViewport(const WebSize&) override;
     void resizePinchViewport(const WebSize&) override;
     void willEndLiveResize() override;
     void didEnterFullScreen() override;
@@ skipping 143 matching lines @@
 #if ENABLE(OILPAN)
     SelfKeepAlive<WebFrameWidgetImpl> m_selfKeepAlive;
 #endif
 };
 
 DEFINE_TYPE_CASTS(WebFrameWidgetImpl, WebFrameWidget, widget, widget->forSubframe(), widget.forSubframe());
 
 } // namespace blink
 
 #endif