Bug 668716 - Change test_bug632379.xul failure on Mac to a todo(); r=orange

layout/generic/test/test_bug632379.xul

@@ -180,7 +180,10 @@ function snapshot(elem)
         synthesizeKey("VK_LEFT", {});
         synthesizeKey("9", {});
     } else {
-        is(pos[1], pos[0], "Popup should open in the same place when the menu is scrolled");
+        // Bug 668716: This test fails on Mac since it was ported to chrome
+        (navigator.platform.indexOf("Mac") == -1 ? is : todo_is)(
+            pos[1], pos[0], "Popup should open in the same place when the menu is scrolled"
+        );
         SimpleTest.finish();
     }
 }