Deal with frame removal by content scripts

extensions/renderer/extension_frame_helper.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 EXTENSIONS_RENDERER_EXTENSION_FRAME_HELPER_H_
 #define EXTENSIONS_RENDERER_EXTENSION_FRAME_HELPER_H_
 
 #include <vector>
 
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
 #include "content/public/common/console_message_level.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "content/public/renderer/render_frame_observer_tracker.h"
 #include "extensions/common/view_type.h"
 
 struct ExtensionMsg_ExternalConnectionInfo;
 struct ExtensionMsg_TabConnectionInfo;
 
 namespace base {
 class ListValue;
 }
 
 namespace extensions {
 
 class Dispatcher;
 struct Message;
 class ScriptContext;
 
 // RenderFrame-level plumbing for extension features.
 class ExtensionFrameHelper
     : public content::RenderFrameObserver,
-      public content::RenderFrameObserverTracker<ExtensionFrameHelper> {
+      public content::RenderFrameObserverTracker<ExtensionFrameHelper>,
+      public base::SupportsWeakPtr<ExtensionFrameHelper> {
  public:
   ExtensionFrameHelper(content::RenderFrame* render_frame,
                        Dispatcher* extension_dispatcher);
   ~ExtensionFrameHelper() override;
 
   // Returns a list of extension RenderFrames that match the given filter
   // criteria. A |browser_window_id| of extension_misc::kUnknownWindowId
   // specifies "all", as does a |view_type| of VIEW_TYPE_INVALID.
   static std::vector<content::RenderFrame*> GetExtensionFrames(
       const std::string& extension_id,
@@ skipping 11 matching lines @@
   // deleted.
   static bool IsContextForEventPage(const ScriptContext* context);
 
   ViewType view_type() const { return view_type_; }
   int tab_id() const { return tab_id_; }
   int browser_window_id() const { return browser_window_id_; }
   bool did_create_current_document_element() const {
     return did_create_current_document_element_;
   }
 
+  // Called when the document element has been inserted in this frame. This
+  // method may invoke untrusted JavaScript code that invalidate the frame and
+  // this ExtensionFrameHelper.
+  void AfterDidCreateDocumentElement();
+
+  // Schedule a callback, to be run at the next AfterDidCreateDocumentElement
+  // notification. Only call this when you are certain that there will be such a
+  // notification, e.g. from RenderFrameObserver::DidCreateDocumentElement.
+  // Otherwise the callback is never invoked, or invoked for a document that you
+  // were not expecting.
+  void ScheduleAfterDidCreateDocumentElement(const base::Closure& callback);
+
  private:
   // RenderFrameObserver implementation.
   void DidCreateDocumentElement() override;
   void DidCreateNewDocument() override;
   void DidMatchCSS(
       const blink::WebVector<blink::WebString>& newly_matching_selectors,
       const blink::WebVector<blink::WebString>& stopped_matching_selectors)
           override;
   void DidCreateScriptContext(v8::Local<v8::Context>,
                               int extension_group,
@@ skipping 32 matching lines @@
   int tab_id_;
 
   // The id of the browser window the render frame is attached to.
   int browser_window_id_;
 
   Dispatcher* extension_dispatcher_;
 
   // Whether or not the current document element has been created.
   bool did_create_current_document_element_;
 
+  // Callbacks to be run at the next AfterDidCreateDocumentElement notification.
+  std::vector<base::Closure> document_element_created_callbacks_;
+
   DISALLOW_COPY_AND_ASSIGN(ExtensionFrameHelper);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_EXTENSION_FRAME_HELPER_H_