Position TV volume UI based on layout orientation.

Previously, the volume UI has been positioned statically on the center
right, however since we don't generally have volume buttons on the
right side like on mobile, we will prioritise reducing content overlap
like we do with other floating windows/panels.

Bug: 246537363
Test: manual, on TV: change volume in LTR -> there should be no change,
switch to an RTL language -> volume dialog should be positioned on the
left and the animation should also have its origin on the left

Change-Id: I64970c50bc58666f99d7fad8f69e9bf6a4bf2936