[DevTools] Cleanup DevToolsTarget and DevToolsManagerDelegate after moving to devtools_discovery.

chrome/browser/android/dev_tools_server.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 CHROME_BROWSER_ANDROID_DEV_TOOLS_SERVER_H_
 #define CHROME_BROWSER_ANDROID_DEV_TOOLS_SERVER_H_
 
 #include <string>
 #include <jni.h>
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 
 namespace devtools_http_handler {
 class DevToolsHttpHandler;
 }
 
-class DevToolsManagerDelegateAndroid;
-
 // This class controls Developer Tools remote debugging server.
 class DevToolsServer {
  public:
   explicit DevToolsServer(const std::string& socket_name_prefix);
   ~DevToolsServer();
 
   // Opens linux abstract socket to be ready for remote debugging.
   void Start(bool allow_debug_permission);
 
   // Closes debugging socket, stops debugging.
   void Stop();
 
   bool IsStarted() const;
 
  private:
   std::string socket_name_;
-  // TODO(dgozman): remove once devtools_discovery component is extracted.
-  scoped_ptr<DevToolsManagerDelegateAndroid> manager_delegate_;
   scoped_ptr<devtools_http_handler::DevToolsHttpHandler> devtools_http_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(DevToolsServer);
 };
 
 bool RegisterDevToolsServer(JNIEnv* env);
 
 #endif  // CHROME_BROWSER_ANDROID_DEV_TOOLS_SERVER_H_