Merge "EventThread: add annotations for mVsyncSchedule" into udc-dev am: 4038250f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/native/+/22236938



Change-Id: Ic420e6aff1b54f3a3a1995a5687b4892092d92c4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>