Merge "Revert "Add discrete contrast UI slider in the setting"" into udc-dev...

Merge "Revert "Add discrete contrast UI slider in the setting"" into udc-dev am: f9f6b80e am: 2aff6c34

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/21733631



Change-Id: I370ec766048281f8cf0cfc7fec3ed7dab51573d7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>