seek
Seeks to the previous segment in the timeline, if such segment exists.
Parameters
snap
If set to true while seeking to a segment that spans across the beginning of the currently visible pages and the previous page(s), the media player will seek inside that segment to match the starting position of the currently visible content. Calling seekToPreviousSegment again will then seek to the beginning of the segment. If set to false, the media player will seek to the beginning of the previous segment.