PPAPI: Add locking for PPB_MessageLoop

ppapi/proxy/ppb_message_loop_proxy.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/proxy/ppb_message_loop_proxy.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
@@ skipping 180 matching lines @@
 }
 
 // static
 void MessageLoopResource::ReleaseMessageLoop(void* value) {
   static_cast<MessageLoopResource*>(value)->DetachFromThread();
 }
 
 // -----------------------------------------------------------------------------
 
 PP_Resource Create(PP_Instance instance) {
+  ProxyAutoLock lock;
   // Validate the instance.
   PluginDispatcher* dispatcher = PluginDispatcher::GetForInstance(instance);
   if (!dispatcher)
     return 0;
   return (new MessageLoopResource(instance))->GetReference();
 }
 
 PP_Resource GetForMainThread() {
+  ProxyAutoLock lock;
   return PluginGlobals::Get()->loop_for_main_thread()->GetReference();
 }
 
 PP_Resource GetCurrent() {
+  ProxyAutoLock lock;
   Resource* resource = MessageLoopResource::GetCurrent();
   if (resource)
     return resource->GetReference();
   return 0;
 }
 
 int32_t AttachToCurrentThread(PP_Resource message_loop) {
   EnterMessageLoop enter(message_loop, true);
   if (enter.succeeded())
     return enter.object()->AttachToCurrentThread();
@@ skipping 40 matching lines @@
 PPB_MessageLoop_Proxy::~PPB_MessageLoop_Proxy() {
 }
 
 // static
 const PPB_MessageLoop_1_0* PPB_MessageLoop_Proxy::GetInterface() {
   return &ppb_message_loop_interface;
 }
 
 }  // namespace proxy
 }  // namespace ppapi