Fixes concurrent display test flakiness am: c3b80dc70b

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

Change-Id: I3deee71a0e007a5e59cddfe8fb1d5e697753bbeb
Signed-off-by: Automerger Merge Worker <[email protected]>