Add separate ContentClient interfaces for gpu/plugin/renderer processes. Since we don't have a n...

content/common/content_client.cc

 // Copyright (c) 2011 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 "content/common/content_client.h"
 
 namespace content {
 
 static ContentClient* g_client;
 
 void SetContentClient(ContentClient* client) {
   g_client = client;
 }
 
 ContentClient* GetContentClient() {
   return g_client;
 }
 
 ContentClient::ContentClient() :
-    browser_client_(NULL) {
+    browser_(NULL), gpu_(NULL), plugin_(NULL), renderer_(NULL) {
 }
 
 ContentClient::~ContentClient() {
 }
 
 }  // namespace content