PPAPI: Don't use MessageLoop::current in the plugin process

ppapi/shared_impl/resource_tracker.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/shared_impl/resource_tracker.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/message_loop/message_loop.h"
 #include "ppapi/shared_impl/callback_tracker.h"
@@ skipping 72 matching lines @@
     LastPluginRefWasDeleted(i->second.first);
 
     // When we go from 1 to 0 plugin ref count, free the additional "real" ref
     // on its behalf. THIS WILL MOST LIKELY RELEASE THE OBJECT AND REMOVE IT
     // FROM OUR LIST.
     i->second.first->Release();
   }
 }
 
 void ResourceTracker::ReleaseResourceSoon(PP_Resource res) {
-  base::MessageLoop::current()->PostNonNestableTask(
+  PpapiGlobals::Get()->GetMainThreadMessageLoop()->PostNonNestableTask(
       FROM_HERE,
       RunWhileLocked(base::Bind(&ResourceTracker::ReleaseResource,
                                 weak_ptr_factory_.GetWeakPtr(),
                                 res)));
 }
 
 void ResourceTracker::DidCreateInstance(PP_Instance instance) {
   CheckThreadingPreconditions();
   // Due to the infrastructure of some tests, the instance is registered
   // twice in a few cases. It would be nice not to do that and assert here
@@ skipping 157 matching lines @@
   if (res == 0)
     return true;
 
   // Skipping the type bits, the least significant bit of |res| should be the
   // same as that of |last_resource_value_|.
   return ((res >> kPPIdTypeBits) & 1) == (last_resource_value_ & 1);
 #endif
 }
 
 }  // namespace ppapi