Merge "Don't start work challenge unless auto-cancel." into udc-dev am: 83b3e82a am: c2911888 am: c12b6fbe am: 9ccaae17

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22965581



Change-Id: I1bc4082602e0633e7065670977a76f670369517f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>