GF-36974: Clear old translation values on controls with preventTransform

If a previously positioned Control has subsequently been marked with preventTransform, we need to clear out any old translation values before positioning with top/left.

This situation arose when adding "disableAcceleration" functionality to moon.Panel and moon.Panels.

Enyo-DCO-1.1-Signed-Off-By: Gray Norton <gray.norton@lge.com>