Bug 577920 - mark DEBUG only variables as ifdef DEBUG in cocoa. r=josh a=joe

widget/src/cocoa/nsMenuX.mm

@@ -199,7 +199,11 @@ nsresult nsMenuX::Create(nsMenuObjectX* aParent, nsMenuGroupOwnerX* aMenuGroupOw
 
   mParent = aParent;
   // our parent could be either a menu bar (if we're toplevel) or a menu (if we're a submenu)
-  nsMenuObjectTypeX parentType = mParent->MenuObjectType();
+
+#ifdef DEBUG
+  nsMenuObjectTypeX parentType =
+#endif
+    mParent->MenuObjectType();
   NS_ASSERTION((parentType == eMenuBarObjectType || parentType == eSubmenuObjectType || parentType == eStandaloneNativeMenuObjectType),
                "Menu parent not a menu bar, menu, or native menu!");