Move the refcounting from the proxy/impl resource object to the shared resource object base class.

ppapi/proxy/plugin_resource.h

Index: ppapi/proxy/plugin_resource.h
diff --git a/ppapi/proxy/plugin_resource.h b/ppapi/proxy/plugin_resource.h
index 703a52994f3d0c144e427b3c3af74844cd3b8b3a..3abe9cbbb703a6b3a352ae212243729d9c817958 100644
--- a/ppapi/proxy/plugin_resource.h
+++ b/ppapi/proxy/plugin_resource.h
@@ -6,7 +6,6 @@
 #define PPAPI_PROXY_PLUGIN_RESOURCE_H_
 
 #include "base/basictypes.h"
-#include "base/memory/ref_counted.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/proxy/host_resource.h"
 #include "ppapi/proxy/plugin_dispatcher.h"
@@ -46,8 +45,7 @@ namespace proxy {
 FOR_ALL_PLUGIN_RESOURCES(DECLARE_RESOURCE_CLASS)
 #undef DECLARE_RESOURCE_CLASS
 
-class PluginResource : public ::ppapi::ResourceObjectBase,
-                       public base::RefCounted<PluginResource> {
+class PluginResource : public ::ppapi::ResourceObjectBase {
  public:
   PluginResource(const HostResource& resource);
   virtual ~PluginResource();