Fix bustage from bug 472674

--HG--
extra : rebase_source : 0eb00dc3d10cff07826736e510eba98144448d84

xpfe/appshell/src/nsContentTreeOwner.cpp

@@ -799,8 +799,8 @@ public:
 
   ~NullJSContextPusher() {
     if (mService) {
-#ifdef DEBUG
       JSContext *cx;
+#ifdef DEBUG
       nsresult rv =
 #endif
         mService->Pop(&cx);