Accessibility focus drawing does not take into account view's transformation matrix.

1.  We are using the view drawing bounds but did not take into account the transformation
    matrix. This leads to showing ugly artifacts on the launcher's hotseat which is
    pretty much the first thing we see.

2. Updated the documentation of View.getDrawingRect to be more explicit that the
   results does not have the transformation matrix applied.

bug:7354033

Change-Id: Ief2e0ea8da05471d71e215ce4497d94ff6e92d1a