Merge "Ignore window manager dumps with no timestamp in timeline" into udc-dev am: 1a4ebace28 am: b2ee95396c

Original change: https://googleplex-android-review.googlesource.com/c/platform/development/+/23660823

Change-Id: I86f787d2990de6023e38bee6d313ca0587ea2386
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>