Merge "Lower per-app notificationchannel limit" into tm-qpr-dev am: 9962ee2c am: ab9b07e9

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19801521



Change-Id: I76c2ef52ae9dc06d801c49442e54b51de8320c0b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>