v5.9.0

• Deprecate encoding_tier and add support for video_quality to replace it
• Add support for premium video quality
• Add support for updating master_access settings on Live Streams
• Add support for view_dropped and view_dropped_percentage
• Remove ad_watch_time and view_content_watch_time, metrics which do not exist.

Note: The above change may be considered breaking; if you were accessing either field on a base Video View, that will no longer work. It is highly likely that your code was not using those fields, however. Additionally, those metrics are no longer allowed in the metrics API.