[automerger skipped] Merge "Add shell background executor to bubbles and put...

[automerger skipped] Merge "Add shell background executor to bubbles and put unregister call on it" into tm-dev am: 0fe75d50 am: a1c5ce59 -s ours am: b1c1fa05 -s ours

am skip reason: Merged-In I2c578d10e0bef49534987be3e82700e50ffd1281 with SHA-1 c679f3d8 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18300851



Change-Id: I270f421fe1a72e94fd8c8257a7eebf58211861dd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>