[DevTools] Implement DevToolsManager::Observer which notifies about target updates.

content/browser/devtools/devtools_agent_host_impl.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/devtools/devtools_agent_host_impl.h"
 
 #include <map>
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 57 matching lines @@
 scoped_refptr<DevToolsAgentHost> DevToolsAgentHost::Create(
     DevToolsExternalAgentProxyDelegate* delegate) {
   return new ForwardingAgentHost(delegate);
 }
 
 void DevToolsAgentHostImpl::AttachClient(DevToolsAgentHostClient* client) {
   scoped_refptr<DevToolsAgentHostImpl> protect(this);
   if (client_) {
     client_->AgentHostClosed(this, true);
     Detach();
-  } else {
-    DevToolsManager::GetInstance()->OnClientAttached();
   }
   client_ = client;
   Attach();
+  DevToolsManager::GetInstance()->AgentHostChanged(this);
 }
 
 void DevToolsAgentHostImpl::DetachClient() {
   if (!client_)
     return;
 
   scoped_refptr<DevToolsAgentHostImpl> protect(this);
   client_ = NULL;
-  DevToolsManager::GetInstance()->OnClientDetached();
   Detach();
+  DevToolsManager::GetInstance()->AgentHostChanged(this);
 }
 
 bool DevToolsAgentHostImpl::IsAttached() {
   return !!client_;
 }
 
 void DevToolsAgentHostImpl::InspectElement(int x, int y) {
 }
 
 std::string DevToolsAgentHostImpl::GetId() {
@@ skipping 15 matching lines @@
 }
 
 void DevToolsAgentHostImpl::HostClosed() {
   if (!client_)
     return;
 
   scoped_refptr<DevToolsAgentHostImpl> protect(this);
   // Clear |client_| before notifying it.
   DevToolsAgentHostClient* client = client_;
   client_ = NULL;
-  DevToolsManager::GetInstance()->OnClientDetached();
   client->AgentHostClosed(this, false);
+  DevToolsManager::GetInstance()->AgentHostChanged(this);
 }
 
 void DevToolsAgentHostImpl::SendMessageToClient(const std::string& message) {
   if (!client_)
     return;
   client_->DispatchProtocolMessage(this, message);
 }
 
 // static
 void DevToolsAgentHost::DetachAllClients() {
   if (g_instances == NULL)
     return;
 
   // Make a copy, since detaching may lead to agent destruction, which
   // removes it from the instances.
   Instances copy = g_instances.Get();
   for (Instances::iterator it(copy.begin()); it != copy.end(); ++it) {
     DevToolsAgentHostImpl* agent_host = it->second;
     if (agent_host->client_) {
       scoped_refptr<DevToolsAgentHostImpl> protect(agent_host);
       // Clear |client_| before notifying it.
       DevToolsAgentHostClient* client = agent_host->client_;
       agent_host->client_ = NULL;
-      DevToolsManager::GetInstance()->OnClientDetached();
       client->AgentHostClosed(agent_host, true);
       agent_host->Detach();
+      DevToolsManager::GetInstance()->AgentHostChanged(protect);
     }
   }
 }
 
 // static
 void DevToolsAgentHost::AddAgentStateCallback(
     const AgentStateCallback& callback) {
   g_callbacks.Get().push_back(&callback);
 }
 
@@ skipping 21 matching lines @@
      (*it)->Run(agent_host, attached);
 }
 
 void DevToolsAgentHostImpl::Inspect(BrowserContext* browser_context) {
   DevToolsManager* manager = DevToolsManager::GetInstance();
   if (manager->delegate())
     manager->delegate()->Inspect(browser_context, this);
 }
 
 }  // namespace content