Problems with displaying/seeking time when track has Infinity duration

[benwiley4000]

I noticed some issues while testing #373. If we are playing an unbounded media stream with Infinity duration, we have an undesirable time progress display:

As we can see for the duration the minute count is Infinity and the second count is NaN. The current time display is unaffected.

However if we begin seeking the currentTime ends up displaying the same way:

And as soon as we try to set the currentTime to the seek time, we encounter a runtime error:

Solution

When the track duration is Infinity, instead of storing that as the duration, we should use the highest known buffered time value and pass that through context as the duration value. If there is no known buffered time value, we will pass 0.

We can store the highestKnownBufferedTime in state when we handle the progress event by extracting the end value at the last index of the bufferedRanges array and returning the max of that and the previous max value.

[benwiley4000]

Going to track currentTime instead of bufferedRanges since in practice these values seem to be roughly the same but the max buffered value increases sporadically, making playback progress look kind of crazy.