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

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

Change-Id: I98530ed986d3160ca6e45972edc8955e2e0bdb55
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>