[1/n] Create flag for PackageManager.USER_MIN_ASPECT_RATIO_APP_DEFAULT

Currently, "App Default" is set to USER_MIN_ASPECT_RATIO_UNSET which
will apply device manufacturer's aspect ratio override over app's
specified aspect ratio.

To introduce pre-selection of fullscreen option when device manufacturer
has applied override, "App default" option needs to be separate from
unset user aspect ratio. "App default" will be set to
USER_MIN_ASPECT_RATIO_APP_DEFAULT instead, which will revert device
manufacturer's fullscreen override if available.

Bug: 310816437
Test: Make
Change-Id: Id5d6a0bdcaa0c08f9d1b2eab7f540bf978a0f7d4