HOVER: Implement hide only on swipe up

    * Add an Y axis HideHelper, just extend current X axis SwipeHelper and
      change interested methods behaviors
    * Some clean up and indenting

    Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>
    Change-Id: I42a260ea993c614b0b9b4558a95dd44dd517c4f1

Change-Id: I9d699ac0a6e632bc1110e93cac9d924611525014