PPAPI: Make blocking completion callbacks work.

ppapi/thunk/ppb_file_ref_thunk.cc

Index: ppapi/thunk/ppb_file_ref_thunk.cc
diff --git a/ppapi/thunk/ppb_file_ref_thunk.cc b/ppapi/thunk/ppb_file_ref_thunk.cc
index 8752b7fb9b79f24261ac801a36b32703f9556005..ea97518190f5ceb5c92664781cca9de212ab6384 100644
--- a/ppapi/thunk/ppb_file_ref_thunk.cc
+++ b/ppapi/thunk/ppb_file_ref_thunk.cc
@@ -66,7 +66,7 @@ int32_t MakeDirectory(PP_Resource directory_ref,
   if (enter.failed())
     return enter.retval();
   return enter.SetResult(enter.object()->MakeDirectory(make_ancestors,
-                                                       callback));
+                                                       enter.callback()));
 }
 
 int32_t Touch(PP_Resource file_ref,
@@ -77,7 +77,7 @@ int32_t Touch(PP_Resource file_ref,
   if (enter.failed())
     return enter.retval();
   return enter.SetResult(enter.object()->Touch(
-      last_access_time, last_modified_time, callback));
+      last_access_time, last_modified_time, enter.callback()));
 }
 
 int32_t Delete(PP_Resource file_ref,
@@ -85,7 +85,7 @@ int32_t Delete(PP_Resource file_ref,
   EnterFileRef enter(file_ref, callback, true);
   if (enter.failed())
     return enter.retval();
-  return enter.SetResult(enter.object()->Delete(callback));
+  return enter.SetResult(enter.object()->Delete(enter.callback()));
 }
 
 int32_t Rename(PP_Resource file_ref,
@@ -94,7 +94,8 @@ int32_t Rename(PP_Resource file_ref,
   EnterFileRef enter(file_ref, callback, true);
   if (enter.failed())
     return enter.retval();
-  return enter.SetResult(enter.object()->Rename(new_file_ref, callback));
+  return enter.SetResult(enter.object()->Rename(new_file_ref,
+                                                enter.callback()));
 }
 
 PP_Var GetAbsolutePath(PP_Resource file_ref) {