Fix a bug where the inspector would not keep event pages alive.

content/browser/debugger/devtools_agent_host.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_DEBUGGER_DEVTOOLS_AGENT_HOST_H_
 #define CONTENT_BROWSER_DEBUGGER_DEVTOOLS_AGENT_HOST_H_
 
 #include <string>
 
 #include "content/common/content_export.h"
@@ skipping 17 matching lines @@
 
   // Sends the message to the devtools agent hosted by this object.
   void Attach();
   void Reattach(const std::string& saved_agent_state);
   void Detach();
   void DipatchOnInspectorBackend(const std::string& message);
   void InspectElement(int x, int y);
   void AddMessageToConsole(ConsoleMessageLevel level,
                            const std::string& message);
 
-  // TODO(yurys): get rid of this method
-  virtual void NotifyClientClosing() = 0;
-
   virtual int GetRenderProcessId() = 0;
 
   void set_close_listener(CloseListener* listener) {
     close_listener_ = listener;
   }
 
  protected:
   DevToolsAgentHost();
   virtual ~DevToolsAgentHost() {}
 
   virtual void SendMessageToAgent(IPC::Message* msg) = 0;
+  virtual void NotifyClientAttaching() = 0;
+  virtual void NotifyClientDetaching() = 0;
+
   void NotifyCloseListener();
 
   CloseListener* close_listener_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_DEBUGGER_DEVTOOLS_AGENT_HOST_H_