Prevent the browser process from creating duplicate RenderViewHosts.

content/browser/renderer_host/render_view_host_delegate.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_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 364 matching lines @@
   // Requests to lock the mouse. Once the request is approved or rejected,
   // GotResponseToLockMouseRequest() will be called on the requesting render
   // view host.
   virtual void RequestToLockMouse(bool user_gesture,
                                   bool last_unlocked_by_target) {}
 
   // Notification that the view has lost the mouse lock.
   virtual void LostMouseLock() {}
 
   // The page is trying to open a new page (e.g. a popup window). The window
-  // should be created associated with the given route, but it should not be
-  // shown yet. That should happen in response to ShowCreatedWindow.
+  // should be created associated with the given |route_id| in process
+  // |render_process_id|, but it should not be shown yet. That should happen in
+  // response to ShowCreatedWindow.
   // |params.window_container_type| describes the type of RenderViewHost
   // container that is requested -- in particular, the window.open call may
   // have specified 'background' and 'persistent' in the feature string.
   //
   // The passed |params.frame_name| parameter is the name parameter that was
   // passed to window.open(), and will be empty if none was passed.
   //
   // Note: this is not called "CreateWindow" because that will clash with
   // the Windows function which is actually a #define.
   virtual void CreateNewWindow(
+      int render_process_id,
       int route_id,
       int main_frame_route_id,
       const ViewHostMsg_CreateWindow_Params& params,
       SessionStorageNamespace* session_storage_namespace) {}
 
   // The page is trying to open a new widget (e.g. a select popup). The
   // widget should be created associated with the given route, but it should
   // not be shown yet. That should happen in response to ShowCreatedWidget.
   // |popup_type| indicates if the widget is a popup and what kind of popup it
   // is (select, autofill...).
@@ skipping 44 matching lines @@
   // created by the RenderViewHost.
   virtual FrameTree* GetFrameTree();
 
  protected:
   virtual ~RenderViewHostDelegate() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_H_