<webview>: Cleanup WebRequest event listeners when embedder destroyed

content/public/browser/browser_plugin_guest_delegate.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_PUBLIC_BROWSER_BROWSER_PLUGIN_GUEST_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_BROWSER_PLUGIN_GUEST_DELEGATE_H_
 
 #include "base/callback_forward.h"
 #include "base/process/kill.h"
 #include "base/strings/string16.h"
@@ skipping 21 matching lines @@
 
   // Request the delegate to close this guest, and do whatever cleanup it needs
   // to do.
   virtual void Close() {}
 
   // Informs the delegate that the guest render process is gone. |status|
   // indicates whether the guest was killed, crashed, or was terminated
   // gracefully.
   virtual void GuestProcessGone(base::TerminationStatus status) {}
 
+  // Informs the delegate that the embedder has been destroyed.
+  virtual void EmbedderDestroyed() {}
+
   virtual bool HandleKeyboardEvent(const NativeWebKeyboardEvent& event);
 
   // Notification that a load in the guest resulted in abort. Note that |url|
   // may be invalid.
   virtual void LoadAbort(bool is_top_level,
                          const GURL& url,
                          const std::string& error_type) {}
 
   // Notification that the guest is no longer hung.
   virtual void RendererResponsive() {}
@@ skipping 15 matching lines @@
       const PermissionResponseCallback& callback);
 
   // Notifies that the content size of the guest has changed in autosize mode.
   virtual void SizeChanged(const gfx::Size& old_size,
                            const gfx::Size& new_size) {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_BROWSER_PLUGIN_GUEST_DELEGATE_H_