Set pillar box bounds in fixed orientation display

Assume a non-resizable fixed portrait activity launched in a fixed
landscape display, the activity should keep its portrait bounds by
fitting the height to display and the width with the same ratio to
height. Previously the pillar box bounds are only set to app bounds
that causes the activity shown in landscape size compat mode. This
change makes them consistent.

Fixes: 158863196
Test: SizeCompatTests#testMoveToDifferentOrientDisplay
Change-Id: Ib7c2b07d9b252a88d2e965cc16ca93f7804b16d0