Merge "Ignore window manager dumps with no timestamp in timeline" into udc-dev am: 1a4ebace28 am: 9f59f382cb am: a2569c37e4

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

Change-Id: I78c7a81cea31759b73a500edd9c05af0a2928487
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>