Merge "Wait for MediaStore idle state to reduce the test flake am: 51fd45cd am: 36f4df55" into tm-d1-dev-plus-aosp am: ad51cda2

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/DocumentsUI/+/18796607



Change-Id: I78b73f6b56528decff8d53b0cd2119dfb4363957
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>