PPAPI: Make blocking completion callbacks work.

ppapi/thunk/ppb_talk_private_thunk.cc

Index: ppapi/thunk/ppb_talk_private_thunk.cc
diff --git a/ppapi/thunk/ppb_talk_private_thunk.cc b/ppapi/thunk/ppb_talk_private_thunk.cc
index 3e3775c4af0f9b09720fe41f552cddad4be9b772..27856883e288d4fb7261a121536c459bb2608a5f 100644
--- a/ppapi/thunk/ppb_talk_private_thunk.cc
+++ b/ppapi/thunk/ppb_talk_private_thunk.cc
@@ -4,6 +4,7 @@
 
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/c/private/ppb_talk_private.h"
+#include "ppapi/shared_impl/tracked_callback.h"
 #include "ppapi/thunk/enter.h"
 #include "ppapi/thunk/ppb_talk_private_api.h"
 #include "ppapi/thunk/thunk.h"
@@ -25,7 +26,7 @@ int32_t GetPermission(PP_Resource resource,
   EnterResource<PPB_Talk_Private_API> enter(resource, true);
   if (enter.failed())
     return PP_ERROR_BADRESOURCE;
-  return enter.object()->GetPermission(callback);
+  return enter.SetResult(enter.object()->GetPermission(enter.callback()));
 }
 
 const PPB_Talk_Private_1_0 g_ppb_talk_private_thunk = {