Clear opener when frame is detached.

third_party/WebKit/public/web/WebFrame.h

 /*
  * Copyright (C) 2009 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 94 matching lines @@
   virtual bool isWebLocalFrame() const = 0;
   virtual WebLocalFrame* toWebLocalFrame() = 0;
   virtual bool isWebRemoteFrame() const = 0;
   virtual WebRemoteFrame* toWebRemoteFrame() = 0;
 
   BLINK_EXPORT bool swap(WebFrame*);
 
   // This method closes and deletes the WebFrame. This is typically called by
   // the embedder in response to a frame detached callback to the WebFrame
   // client.
-  virtual void close() = 0;
+  virtual void close();
 
   // Called by the embedder when it needs to detach the subtree rooted at this
   // frame.
   BLINK_EXPORT void detach();
 
   // Basic properties ---------------------------------------------------
 
   // The unique name of this frame.
   virtual WebString uniqueName() const = 0;
 
@@ skipping 306 matching lines @@
   // Returns the frame inside a given frame or iframe element. Returns 0 if
   // the given element is not a frame, iframe or if the frame is empty.
   BLINK_EXPORT static WebFrame* fromFrameOwnerElement(const WebElement&);
 
 #if BLINK_IMPLEMENTATION
   static WebFrame* fromFrame(Frame*);
 
   bool inShadowTree() const { return m_scope == WebTreeScopeType::Shadow; }
 
   static void traceFrames(Visitor*, WebFrame*);
-  void clearWeakFrames(Visitor*);
 #endif
 
  protected:
   explicit WebFrame(WebTreeScopeType);
   virtual ~WebFrame();
 
   // Sets the parent WITHOUT fulling adding it to the frame tree.
   // Used to lie to a local frame that is replacing a remote frame,
   // so it can properly start a navigation but wait to swap until
   // commit-time.
   void setParent(WebFrame*);
 
  private:
 #if BLINK_IMPLEMENTATION
   friend class OpenedFrameTracker;
   friend class WebFrameTest;
 
   static void traceFrame(Visitor*, WebFrame*);
-  static bool isFrameAlive(const WebFrame*);
 #endif
 
   const WebTreeScopeType m_scope;
 
   WebFrame* m_parent;
   WebFrame* m_previousSibling;
   WebFrame* m_nextSibling;
   WebFrame* m_firstChild;
   WebFrame* m_lastChild;
 
   WebFrame* m_opener;
   std::unique_ptr<OpenedFrameTracker> m_openedFrameTracker;
 };
 
 }  // namespace blink
 
 #endif