Merge "Add One-handed mode entry point in a11y system controls" into sc-dev...

Merge "Add One-handed mode entry point in a11y system controls" into sc-dev am: 1da2a539 am: b848c52f am: a720c45b

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/14980884

Change-Id: I9b4dc15d5e66dc6f2fabf8ea3bb378e80a6606a5