Deal with frame removal by content scripts

content/public/renderer/content_renderer_client.h

 // Copyright (c) 2012 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_RENDERER_CONTENT_RENDERER_CLIENT_H_
 #define CONTENT_PUBLIC_RENDERER_CONTENT_RENDERER_CLIENT_H_
 
 #include <stddef.h>
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/memory/weak_ptr.h"
 #include "base/strings/string16.h"
 #include "content/public/common/content_client.h"
 #include "third_party/WebKit/public/platform/WebPageVisibilityState.h"
 #include "third_party/WebKit/public/web/WebNavigationPolicy.h"
 #include "third_party/WebKit/public/web/WebNavigationType.h"
 #include "ui/base/page_transition_types.h"
 #include "v8/include/v8.h"
 
 class GURL;
 class SkBitmap;
@@ skipping 270 matching lines @@
   // Allows an embedder to provide a blink::WebAppBannerClient.
   virtual scoped_ptr<blink::WebAppBannerClient> CreateAppBannerClient(
       RenderFrame* render_frame);
 
   // Gives the embedder a chance to add properties to the context menu.
   // Currently only called when the context menu is for an image.
   virtual void AddImageContextMenuProperties(
       const blink::WebURLResponse& response,
       std::map<std::string, std::string>* properties) {}
 
+  // Notifies that a document element has been inserted in the frame's document.
+  // This may be called multiple times for the same document. This method may
+  // invalidate the frame.

[esprehn, 2016/02/17 01:43:47]

This should be specific to extensions, This should be
NotifyExtensionsAfterDidCreateDocumentElement.

+  virtual void AfterDidCreateDocumentElement(RenderFrame* render_frame) {}
+
+  // Notifies that the DOM is ready in the frame's document.
+  // This method may invalidate the frame.
+  virtual void AfterDidFinishDocumentLoad(RenderFrame* render_frame) {}

[esprehn, 2016/02/17 01:43:47]

ditto

+
   // Notifies that a service worker context has been created. This function
   // is called from the worker thread.
   virtual void DidInitializeServiceWorkerContextOnWorkerThread(
       v8::Local<v8::Context> context,
       const GURL& url) {}
 
   // Notifies that a service worker context will be destroyed. This function
   // is called from the worker thread.
   virtual void WillDestroyServiceWorkerContextOnWorkerThread(
       v8::Local<v8::Context> context,
       const GURL& url) {}
 
   // Whether this renderer should enforce preferences related to the WebRTC
   // routing logic, i.e. allowing multiple routes and non-proxied UDP.
   virtual bool ShouldEnforceWebRTCRoutingPreferences();
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_CONTENT_RENDERER_CLIENT_H_