private com.google.protobuf.RepeatedFieldBuilderV3<
            com.google.cloud.video.stitcher.v1.Event,
            com.google.cloud.video.stitcher.v1.Event.Builder,
            com.google.cloud.video.stitcher.v1.EventOrBuilder>
        getActivityEventsFieldBuilder() {
      if (activityEventsBuilder_ == null) {
        activityEventsBuilder_ =
            new com.google.protobuf.RepeatedFieldBuilderV3<
                com.google.cloud.video.stitcher.v1.Event,
                com.google.cloud.video.stitcher.v1.Event.Builder,
                com.google.cloud.video.stitcher.v1.EventOrBuilder>(
                activityEvents_,
                ((bitField0_ & 0x00000004) != 0),
                getParentForChildren(),
                isClean());
        activityEvents_ = null;
      }
      return activityEventsBuilder_;
    }
<pre>
The list of progress tracking events for the ad break. These can be of
the following IAB types: `MUTE`, `UNMUTE`, `PAUSE`, `CLICK`,
`CLICK_THROUGH`, `REWIND`, `RESUME`, `ERROR`, `FULLSCREEN`,
`EXIT_FULLSCREEN`, `EXPAND`, `COLLAPSE`, `ACCEPT_INVITATION_LINEAR`,
`CLOSE_LINEAR`, `SKIP`.
</pre>

<code>repeated .google.cloud.video.stitcher.v1.Event activity_events = 3;</code>
java-video-stitcher/proto-google-cloud-video-stitcher-v1/src/main/java/com/google/cloud/video/stitcher/v1/VodSessionAd.java