[automerger skipped] Add Flaky annotation to 4 flaky tests in VibratorManagerServiceTest am: a1fbf22001 -s ours am: b30734917a -s ours

am skip reason: Merged-In If7c7a2c94db3eac4f4bc79a6c05c35683031a50c with SHA-1 ea84d650b1 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24720959

Change-Id: I976f84b8971afd660a664ef3d52522e670791152
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>