Task Manager should listen to WebContentsObserver::RenderFrameCreated.

content/browser/renderer_host/render_view_host_impl.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_IMPL_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 96 matching lines @@
   void NotifyMoveOrResizeStarted() override;
   void SetWebUIProperty(const std::string& name,
                         const std::string& value) override;
   void SyncRendererPrefs() override;
   WebPreferences GetWebkitPreferences() override;
   void UpdateWebkitPreferences(const WebPreferences& prefs) override;
   void OnWebkitPreferencesChanged() override;
   void SelectWordAroundCaret() override;
 
   // RenderProcessHostObserver implementation
-  void RenderProcessReady(RenderProcessHost* host) override;
   void RenderProcessExited(RenderProcessHost* host,
                            base::TerminationStatus status,
                            int exit_code) override;
 
   void set_delegate(RenderViewHostDelegate* d) {
     CHECK(d);  // http://crbug.com/82827
     delegate_ = d;
   }
 
   // Set up the RenderView child process. Virtual because it is overridden by
@@ skipping 190 matching lines @@
   // ClosePage() until either the render process ACKs the close with an IPC to
   // OnClosePageACK(), or until the timeout triggers and the page is forcibly
   // closed.
   std::unique_ptr<TimeoutMonitor> close_timeout_;
 
   // This monitors input changes so they can be reflected to the interaction MQ.
   std::unique_ptr<InputDeviceChangeObserver> input_device_change_observer_;
 
   bool updating_web_preferences_;
 
-  bool render_view_ready_on_process_launch_;
-
   base::WeakPtrFactory<RenderViewHostImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderViewHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_IMPL_H_