Check for text track changes that occurred before tech was listening

[gesinger]

If any code sets a track mode during player setup (e.g., track.mode = 'showing') for non native text tracks, there is a race case where the player may not be listening for changes on the track. For instance:

var player = videojs('my-video', {
    html5: {
        nativeTextTracks: false
    }
});

var track = player.addTextTrack('captions');
track.mode = 'showing';

The caption settings will show the captions as on for the track, but the captions will not show up on the video unless a user switches to fullscreen or changes the caption settings (both will update display appropriately).

This change ensures that before videojs starts listening to change events on tracks, it gets any changes that may have happened between then and the start of setup.

[pam]

Tests passed. Automated cross-browser testing via Sauce Labs and Travis CI shows that the JavaScript changes in this pull request are: CONFIRMED

Commit: 8a3a97ecc936e34ca052570e4efb14ea1d8e1e45
Build details: https://travis-ci.org/pam/video.js/builds/92385457

(Please note that this is a fully automated comment.)

[gkatsev]

What if the original value was true?

[gesinger]

Good call. Will store the original value and reset it here.

[pam]

Tests passed. Automated cross-browser testing via Sauce Labs and Travis CI shows that the JavaScript changes in this pull request are: CONFIRMED

Commit: dc174d890bef253d042e086aa8add0986afac9d9
Build details: https://travis-ci.org/pam/video.js/builds/92431612

(Please note that this is a fully automated comment.)

[gkatsev]

LGTM

[dmlap]

Is this necessary? Seems like this function could not run unless tracks was already defined at the assignment in emulateTextTracks above.

[gkatsev]

It isn't strictly necessary but it makes testing this significantly easier.

[pam]

Tests passed. Automated cross-browser testing via Sauce Labs and Travis CI shows that the JavaScript changes in this pull request are: CONFIRMED

Commit: b02fdef
Build details: https://travis-ci.org/pam/video.js/builds/92834268

(Please note that this is a fully automated comment.)

[gkatsev]

Sweet, that test looks a lot nicer now too.

[gkatsev]

LGTM

[mmcc]

Lgtm!