Defines a set of methods that a video player must implement to be used by the IMA SDK for
dynamic ad insertion.
Defines an interface to allow SDK to track progress of the content video. It provides
updates required to enable triggering ads at configured cue points.
Gets an update on the progress of the video.
The function must not return a null value.
Use VideoProgressUpdate.VIDEO_TIME_NOT_READY if the current time is not
available.