Tooltip: Fix default for position option, follow-up to 1d9eab1.

Author: jzaefferer

tests/unit/tooltip/tooltip_common.js

@@ -7,7 +7,7 @@ TestHelpers.commonWidgetTests( "tooltip", {
 position: {
 my: "left top+15",
 at: "left bottom",
-collision: "flipfit flipfit"
+collision: "flipfit flip"
 },
 show: true,
 tooltipClass: null,