Merge "Use an isolated token to represent shell transitions" into tm-qpr-dev am: e7aef726bb am: c702e39376

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/20583342

Change-Id: Id269f04e14ace256fad8e96764ae54a931d357e7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>