[automerger skipped] DO NOT MERGE Prevent apps from creating blocked channel groups am: b993531c am: d761dbd9 -s ours am: 8b386cd9 -s ours

am skip reason: subject contains skip directive

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16621952

Change-Id: If70b13ac707b10106482d267e1ce6bbbf6109c62