Fixes concurrent display test flakiness am: c3b80dc7 am: e3f0e8ae

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22656860



Change-Id: I65f009a2441a471ad1d1641e9345b2d21db04b2b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>