base::RefCounted now DCHECKs when referenced from multiple threads.

ppapi/shared_impl/resource.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.
 
 #ifndef PPAPI_SHARED_IMPL_RESOURCE_H_
 #define PPAPI_SHARED_IMPL_RESOURCE_H_
 
 #include <stddef.h>  // For NULL.
 
 #include <string>
@@ skipping 100 matching lines @@
 FOR_ALL_PPAPI_RESOURCE_APIS(DECLARE_RESOURCE_CLASS)
 #undef DECLARE_RESOURCE_CLASS
 }  // namespace thunk
 
 // Resources have slightly different registration behaviors when the're an
 // in-process ("impl") resource in the host (renderer) process, or when they're
 // a proxied resource in the plugin process. This enum differentiates those
 // cases.
 enum ResourceObjectType { OBJECT_IS_IMPL, OBJECT_IS_PROXY };
 
-class PPAPI_SHARED_EXPORT Resource : public base::RefCounted<Resource> {
+// TODO(mgiuca): Avoid using UnsafeRefCounted. http://crbug.com/469952.
+class PPAPI_SHARED_EXPORT Resource : public base::UnsafeRefCounted<Resource> {
  public:
   // Constructor for impl and non-proxied, instance-only objects.
   //
   // For constructing "impl" (non-proxied) objects, this just takes the
   // associated instance, and generates a new resource ID. The host resource
   // will be the same as the newly-generated resource ID. For all objects in
   // the renderer (host) process, you'll use this constructor and call it with
   // OBJECT_IS_IMPL.
   //
   // For proxied objects, this will create an "instance-only" object which
@@ skipping 120 matching lines @@
   template <>                                 \
   inline thunk::RESOURCE* Resource::GetAs() { \
     return As##RESOURCE();                    \
   }
 FOR_ALL_PPAPI_RESOURCE_APIS(DEFINE_RESOURCE_CAST)
 #undef DEFINE_RESOURCE_CAST
 
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_RESOURCE_H_