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: I5e19c1ec324bb099b0a5d966cb2fd934393c28e7