[DevTools] Migrate from AgentStateCallbacks to DevToolsAgentHostObserver.

chrome/browser/android/devtools_manager_delegate_android.cc

 // Copyright 2015 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 "chrome/browser/android/devtools_manager_delegate_android.h"
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 241 matching lines @@
   return DevToolsAgentHost::Forward(
       base::IntToString(tab->GetAndroidId()),
       base::WrapUnique(new TabProxyDelegate(tab)));
 }
 
 std::string DevToolsManagerDelegateAndroid::GetDiscoveryPageHTML() {
   return ResourceBundle::GetSharedInstance().GetRawDataResource(
       IDR_DEVTOOLS_DISCOVERY_PAGE_HTML).as_string();
 }
 
-void DevToolsManagerDelegateAndroid::DevToolsAgentStateChanged(
-    DevToolsAgentHost* agent_host, bool attached) {
-  network_protocol_handler_->DevToolsAgentStateChanged(agent_host, attached);
+void DevToolsManagerDelegateAndroid::DevToolsAgentHostAttached(
+    content::DevToolsAgentHost* agent_host) {
+  network_protocol_handler_->DevToolsAgentStateChanged(agent_host, true);
 }
+
+void DevToolsManagerDelegateAndroid::DevToolsAgentHostDetached(
+    content::DevToolsAgentHost* agent_host) {
+  network_protocol_handler_->DevToolsAgentStateChanged(agent_host, false);
+}