fix: audio segment on incorrect timeline

Description

Currently there is an edge case in DASH where certain points of audio segments and video segments do not always exist on the same timeline.

Example: We seek to 100 seconds into the video. There is an audio segment that is from 98-100.25 seconds, and the video segment is from 100-109.95. The audio segment is on a timeline from 90-99.99, and the video segment is on a timeline from 110-119.99. We fall into a loop in this scenario because VHS catches that we have bad timelines, but we do not do anything to fix it in this scenario.

This change allows us to check for this specific scenario. When we attempt to load an audio segment that is on a prior timeline to the video segment, we will now force the player forward to just past the faulty audio segment. This ensures that the audio and video segments will now be on the same timeline.

Specific Changes proposed

Moves the fixBadTimeline logic outside of the hasEnoughInfoToLoad_ and hasEnoughInfoToAppend_ functions so we do not have unexpected actions on a function that should just return a boolean.
Create an event for when the audio segment is on a prior timeline to what the main video segment is on.
Update the pending audio timeline change, and set the currentTime to just after the end of the faulty audio segment.

Requirements Checklist

[ ] Feature implemented / Bug fixed
[ ] If necessary, more likely in a feature request than a bug fix
- [ ] Unit Tests updated or fixed
- [ ] Docs/guides updated
- [ ] Example created (starter template on JSBin)
[ ] Reviewed by Two Core Contributors

videojs / http-streaming