[PPAPI] ResourceVar now reference counts its PP_Resource in the plugin.

ppapi/proxy/plugin_var_tracker.cc

Index: ppapi/proxy/plugin_var_tracker.cc
diff --git a/ppapi/proxy/plugin_var_tracker.cc b/ppapi/proxy/plugin_var_tracker.cc
index ee299852514c865e85e08b5554db8c6251334f68..d2a4d74d0e3eaa34502beaace129e9e9d983c16b 100644
--- a/ppapi/proxy/plugin_var_tracker.cc
+++ b/ppapi/proxy/plugin_var_tracker.cc
@@ -10,10 +10,13 @@
 #include "ppapi/c/ppb_var.h"
 #include "ppapi/proxy/plugin_array_buffer_var.h"
 #include "ppapi/proxy/plugin_dispatcher.h"
+#include "ppapi/proxy/plugin_resource_var.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/proxy_object_var.h"
 #include "ppapi/shared_impl/api_id.h"
+#include "ppapi/shared_impl/ppapi_globals.h"
 #include "ppapi/shared_impl/proxy_lock.h"
+#include "ppapi/shared_impl/resource_tracker.h"
 #include "ppapi/shared_impl/var.h"
 
 namespace ppapi {
@@ -151,6 +154,14 @@ void PluginVarTracker::ReleaseHostObject(PluginDispatcher* dispatcher,
   ReleaseVar(found->second);
 }
 
+ResourceVar* PluginVarTracker::MakeResourceVar(PP_Resource pp_resource) {
+  ResourceTracker* resource_tracker = PpapiGlobals::Get()->GetResourceTracker();
+  ppapi::Resource* resource = resource_tracker->GetResource(pp_resource);
+  if (!resource)
+    return NULL;
+  return new PluginResourceVar(resource);
+}
+
 void PluginVarTracker::DidDeleteInstance(PP_Instance instance) {
   // Calling the destructors on plugin objects may in turn release other
   // objects which will mutate the map out from under us. So do a two-step