remoting: Cleanup class/struct fwd declarations

remoting/host/native_messaging/pipe_messaging_channel.h

 // Copyright 2014 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 REMOTING_HOST_NATIVE_MESSAGING_PIPE_MESSAGING_CHANNEL_H_
 #define REMOTING_HOST_NATIVE_MESSAGING_PIPE_MESSAGING_CHANNEL_H_
 
 #include <memory>
 
 #include "base/callback.h"
 #include "base/files/file.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/non_thread_safe.h"
 #include "extensions/browser/api/messaging/native_messaging_channel.h"
 #include "remoting/host/native_messaging/native_messaging_reader.h"
 #include "remoting/host/native_messaging/native_messaging_writer.h"
 
 namespace base {
-class DictionaryValue;
 class Value;
 }  // namespace base
 
 namespace remoting {
 
 // An implementation of extensions::NativeMessagingChannel using a pipe. It
 // is used by the It2MeNativeMessagingHost and Me2MeNativeMessagingHost to
 // communicate with the chrome process.
 // TODO(kelvinp): Move this class to the extensions/browser/api/messaging
 // directory.
@@ skipping 24 matching lines @@
   EventHandler* event_handler_;
   base::WeakPtr<PipeMessagingChannel> weak_ptr_;
   base::WeakPtrFactory<PipeMessagingChannel> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PipeMessagingChannel);
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_HOST_NATIVE_MESSAGING_PIPE_MESSAGING_CHANNEL_H_