Set textDirection=locale and layoutDirection=locale for alert dialog

It's strongly recommended by internationalization team to set
android:textDirection="locale" and android:layoutDirection="locale" to
tackle a text that consists of RTL and LTR characters.

Bug: 279491415
Bug: 283608580
Bug: 283608637
Test: manual

Merged-In: I0dfa0da22e70d267d8d8ed8e9c5be3d6db107841
Change-Id: I0dfa0da22e70d267d8d8ed8e9c5be3d6db107841
(cherry picked from commit 219d4e6c)