Refactor some ResourceMessageReply usages.

ppapi/host/host_message_context.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 "ppapi/host/host_message_context.h"
 
 namespace ppapi {
 namespace host {
 
-ReplyMessageContext::ReplyMessageContext() {
-}
+ReplyMessageContext::ReplyMessageContext()
+    : sync_reply_msg(NULL), routing_id(MSG_ROUTING_NONE) {}
 
 ReplyMessageContext::ReplyMessageContext(
     const ppapi::proxy::ResourceMessageReplyParams& cp,
     IPC::Message* sync_reply_msg,
     int routing_id)
     : params(cp),
       sync_reply_msg(sync_reply_msg),
       routing_id(routing_id) {
 }
 
@@ skipping 27 matching lines @@
 }
 
 ReplyMessageContext HostMessageContext::MakeReplyMessageContext() const {
   ppapi::proxy::ResourceMessageReplyParams reply_params(params.pp_resource(),
                                                         params.sequence());
   return ReplyMessageContext(reply_params, sync_reply_msg, routing_id);
 }
 
 }  // namespace host
 }  // namespace ppapi