Merge "Fix settings page flicker in two ways: 1. On create use UiBlocker as recommended by settings team 2. On resume only update the preferences list if the system setting has    changed." into tm-dev am: 798a0fab9c

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/17219772

Change-Id: Ib17152dbc29a9cc0588607966da310e53cdba4bb