add missing headers in ppapi/*

ppapi/proxy/dispatch_reply_message.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.
 
 // This file provides infrastructure for dispatching messasges from host
 // resource, inlcuding reply messages or unsolicited replies. Normal IPC Reply
 // handlers can't take extra parameters. We want to take a
 // ResourceMessageReplyParams as a parameter.
 
 #ifndef PPAPI_PROXY_DISPATCH_REPLY_MESSAGE_H_
 #define PPAPI_PROXY_DISPATCH_REPLY_MESSAGE_H_
 
+#include "base/callback.h"
 #include "base/profiler/scoped_profile.h"  // For TRACK_RUN_IN_IPC_HANDLER.
 #include "ipc/ipc_message_macros.h"
 #include "ppapi/c/pp_errors.h"
 
 namespace ppapi {
 namespace proxy {
 
 class ResourceMessageReplyParams;
 
 template <class ObjT, class Method>
@@ skipping 131 matching lines @@
 #define PPAPI_DISPATCH_PLUGIN_RESOURCE_CALL_UNHANDLED(code) \
     default: { \
         code; \
     } \
     break;
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_DISPATCH_REPLY_MESSAGE_H_