Merge "Remove unused notification pipeline flag code" into tm-qpr-dev am: 241b46e6 am: d05f2ef3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20176971



Change-Id: If1e159db2f43e0148879fa314ffa88a5348653df
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>