Note that STYLE and REGION are not supported in mp4 container due to
spec limitation as 14496-30:2014 does not specify a way to signal
styles/regions inside mp4.
Closes#344.
Change-Id: I05c14df916f7b2c7ca4364ee9407e0eda4dc7a3f
Created end-to-end tests for the segmented webvtt text in HLS. The
text stream is longer than both audio and video, so there are more
text segments than video/audio.
Change-Id: Ib860ccd3f2ac0048983fdeebe3847a0b9dcbc160