Don't allow RenderFrames to be created during WebContents destruction.

content/browser/frame_host/render_frame_host_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_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
 #define CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 283 matching lines @@
   virtual bool ShouldAllowRunningInsecureContent(WebContents* web_contents,
                                                  bool allowed_per_prefs,
                                                  const url::Origin& origin,
                                                  const GURL& resource_url);
 
 #if defined(OS_ANDROID)
   virtual base::android::ScopedJavaLocalRef<jobject>
   GetJavaRenderFrameHostDelegate();
 #endif
 
+  // Whether the delegate is being destroyed, in which case the RenderFrameHost
+  // should not be asked to create a RenderFrame.
+  virtual bool IsBeingDestroyed() const;
+
  protected:
   virtual ~RenderFrameHostDelegate() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_DELEGATE_H_