Developer option to force RTL layout

Make sure screen layout changes are taken into account in Configuration diffs.
Initialize the SystemProperty from Global settings on startup of
ActivityManagerService.

TextUtils checks the override flag to decide if the default layout direction
should be forced to RTL.

Bug: 10244047
Change-Id: I23a2583d790a355060d0d898ba44e5f7dc896b46
4 files changed