Fix undefined fragData when using parsed manifest object

[AlecAnthonyGarcia]

Fixes #2088

When you initialize the stream with a parsed manifest object instead of the URL of a MPD, getStreamStartTime in PlaybackController tries to get the parsed media fragments but it's undefined since the parsing is never done for a parsed manifest object, it's only parsed from the URL of an MPD.

Example manifest that is passed in as a string to the parser: https://gist.github.com/CaliAlec/4ae753844344aab7da98e2418b22a624

In order to parse the manifest string, I'm using internal classes:

const manifest = MANIFEST_STRING;
const parser = DashParser().create();
const xlink = XLinkController().create({});
const mpd = parser.parse(manifest, xlink);

[AlecAnthonyGarcia]

Any issues with this pull request?

[davemevans]

There are a load of isNaN(startTimeOffset) checks below here. Why has the initial value changed to 0 - surely, at least if ignoreStartTimeOffset is true, it should still be NaN?

[AlecAnthonyGarcia]

In my case, when loading a parsed manifest object, if startTimeOffset is NaN, I will get the following error: Uncaught TypeError: Failed to set the 'currentTime' property on 'HTMLMediaElement': The provided double value is non-finite.

It needs to be 0 so that the stream starts from the beginning. I guess a better approach would be to leave the initial value as NaN, and if fragData is null, set startTimeOffset to 0?

[AlecAnthonyGarcia]

I reverted the initial value and only set it to 0 if fragData is null

[dsparacio]

It is not pulled in yet because there is concern for regression here. There are so many use cases around that code for Multiperiod, live starttime, anchor points etc.

What streams have you tested with? Can you ensure that it works with all streams in the first three sub folders of this player (VOD, Live and Subtitles)?
http://reference.dashif.org/dash.js/nightly/samples/dash-if-reference-player/index.html

[dsparacio]

I take my comment back you are just protecting against null value so I am going to pull in. Thanks for the commit;

[AlecAnthonyGarcia]

@AkamaiDASH Cool, thanks. Could I please have an ETA on the release of the next version on NPM?

[dsparacio]

We are targeting to release NPM and tagged Github release no later than Sept 1st pending any major issue found in next two weeks of testing.