Allow the default mode for video peek to be undefined am: f3e84296

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/18579465



Change-Id: I2e4fb9260150b10ac1fbc7999103804fd9b6fac9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>