feat: Render native cues using text displayer

[tykus160]

Closes #2585

Ownership of text displayer has changed to player, it is created now in MSE mode and in src= mode if video element has textTracks property.

[shaka-bot]

Incremental code coverage: 52.48%

[gkatsev]

The changes here seem reasonable. The only thing I think we should have is an option to use native text track rendering. This is because on safari, if you use native pip, it will continue displaying captions if they are natively rendered. But not if they are rendered manually.
Even better if the option can be toggled at runtime so that native rendering could be toggled as part of a pip requested event handler.

[avelad]

The changes here seem reasonable. The only thing I think we should have is an option to use native text track rendering. This is because on safari, if you use native pip, it will continue displaying captions if they are natively rendered. But not if they are rendered manually. Even better if the option can be toggled at runtime so that native rendering could be toggled as part of a pip requested event handler.

I prefer that we detect if we are in PiP and switch to native mode. But this only applies if we use the PiP of the video, not the document. See: https://github.com/shaka-project/shaka-player/blob/main/ui/pip_button.js

[gkatsev]

I prefer that we detect if we are in PiP and switch to native mode.

👍🏻, doing it automatically, sounds good to me.

But this only applies if we use the PiP of the video, not the document

💯. Though, only safari does it properly and shows captions in the video pip. Firefox will as well, but they don't implement the pip api, so, not possible to know when entering pip, i believe.

[avelad]

But this only applies if we use the PiP of the video, not the document

💯. Though, only safari does it properly and shows captions in the video pip. Firefox will as well, but they don't implement the pip api, so, not possible to know when entering pip, i believe.

And do you know if Firefox shows subtitles in its PiP?

[gkatsev]

yeah, firefox shows captions in its pip. They were the first to implement that.

[avelad]

yeah, firefox shows captions in its pip. They were the first to implement that.

Well, since Firefox does not follow the PiP standard, in this case Firefox would be left without subtitles.