fix: fix onProgress callback not firing during iOS live streams

[ecozoic]

I noticed that the onProgress callback only gets fired once during live streams on iOS. This is because, on iOS, player.duration returns Infinity for live streams. Since it always returns Infinity, the progress timeout short-circuits and so the callback stops firing altogether.

I have recently had to fix this issue in a few other places, and I have found that using player.seekable.end(0) works great as an alternative. It returns the same thing as player.duration, but works on iOS as well.

In order to minimize the potential impact of this change, I explicitly check for Infinity and only then do I return player.seekable.end(0). Otherwise I continue to return value of the duration property.

Let me know if you need me to me make any updates!

[ecozoic]

Made some minor updates to improve this fix. While seekable should almost always be contiguous anyway, I now make sure to grab the LAST seekable timeRange and no longer make the assumption that it will always be at 0 index. Also added a bit of defensive programming to make sure we don't attempt to access end when seekable has 0 length (before a video is initialized/has a source for example). This would throw an error.

[cookpete]

Nice work! Sorry for the delay on this.