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

content/browser/debugger/devtools_agent_host.cc

 // 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.
 
 #include "content/browser/debugger/devtools_agent_host.h"
 
 #include "base/basictypes.h"
 #include "content/common/devtools_messages.h"
 
 namespace content {
 
 DevToolsAgentHost::DevToolsAgentHost() : close_listener_(NULL) {
 }
 
 void DevToolsAgentHost::Attach() {
   SendMessageToAgent(new DevToolsAgentMsg_Attach(MSG_ROUTING_NONE));
+  NotifyClientAttaching();
 }
 
 void DevToolsAgentHost::Reattach(const std::string& saved_agent_state) {
   SendMessageToAgent(new DevToolsAgentMsg_Reattach(
       MSG_ROUTING_NONE,
       saved_agent_state));
+  NotifyClientAttaching();
 }
 
 void DevToolsAgentHost::Detach() {
   SendMessageToAgent(new DevToolsAgentMsg_Detach(MSG_ROUTING_NONE));
+  NotifyClientDetaching();
 }
 
 void DevToolsAgentHost::DipatchOnInspectorBackend(const std::string& message) {
   SendMessageToAgent(new DevToolsAgentMsg_DispatchOnInspectorBackend(
       MSG_ROUTING_NONE, message));
 }
 
 void DevToolsAgentHost::InspectElement(int x, int y) {
   SendMessageToAgent(new DevToolsAgentMsg_InspectElement(MSG_ROUTING_NONE,
                                                          x, y));
 }
 
 void DevToolsAgentHost::AddMessageToConsole(ConsoleMessageLevel level,
                                             const std::string& message) {
   SendMessageToAgent(new DevToolsAgentMsg_AddMessageToConsole(
       MSG_ROUTING_NONE,
       level,
       message));
 }
 
 void DevToolsAgentHost::NotifyCloseListener() {
   if (close_listener_) {
     close_listener_->AgentHostClosing(this);
     close_listener_ = NULL;
   }
 }
 
 }  // namespace content