[automerger skipped] DO NOT MERGE Prevent apps from creating blocked channel groups am: b993531c0d am: d761dbd934 -s ours am: 8b386cd940 -s ours am: 882759b36e -s ours am: a4845db3d8 -s ours am: c6e54cabfc -s ours am: 57f9ed0c05 -s ours am: 8a1cb7520b -s ours

am skip reason: subject contains skip directive

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

Change-Id: I7c65f52e5d85899bb4f01cd37bc332474a3bba28