fix(AU-2128): Let 'en' be selected as transcript by default when youtube video

[Rodra]

AU-2128

Description

Let english transcript be selected by default in video player despite transcript not available in transcripts["transcripts"] but available in transcripts["sub"].

Current Behavior
https://www.loom.com/share/a4e31efd83d8418f9577f3e43c9a5721?sid=34060663-e8dc-456a-a49d-ea163b650c4d

New Behavior
https://www.loom.com/share/c7cf07c1440942c893e7287496b83b7b?sid=bec454c3-7685-4dca-9970-daf341d64c43

Testing instructions

Deadline

Other information

[nsprenkle]

@Rodra , could you add some comments here to explain the logic, I'm finding it hard to parse through.

[Rodra]

@Rodra , could you add some comments here to explain the logic, I'm finding it hard to parse through.

Sure, this new condition when selecting the default transcript is the one that does the trick https://github.com/openedx/edx-platform/pull/35116/files#diff-a7e3c5a7f8c78b1241f3617e180bc1976ac83b45e804055e4a677eed0bca87e4R872.

Since at this point of the code https://github.com/openedx/edx-platform/pull/35116/files#diff-a7e3c5a7f8c78b1241f3617e180bc1976ac83b45e804055e4a677eed0bca87e4L867 other_langs is a list that doesn't have english (because is not part of that list if it's a youtube video), we were skipping the first condition of the if (https://github.com/openedx/edx-platform/pull/35116/files#diff-a7e3c5a7f8c78b1241f3617e180bc1976ac83b45e804055e4a677eed0bca87e4L867) and the transcript language selected ends up being the one that was set prior to triggering this action (https://github.com/openedx/edx-platform/pull/35116/files#diff-a7e3c5a7f8c78b1241f3617e180bc1976ac83b45e804055e4a677eed0bca87e4L871).

But I noticed that english IS being added to the transcript options of the video player, but a little bit later in here https://github.com/openedx/edx-platform/blob/master/xmodule/video_block/video_block.py#L191. So I just reused this condition to select transcript as default even if english is not inside of the transcript options list yet. Because I'm sure it will be added later.

[rayzhou-bit]

lgtm!

[edx-pipeline-bot]

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[edx-pipeline-bot]

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[edx-pipeline-bot]

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[edx-pipeline-bot]

2U Release Notice: This PR has been rolled back from the edX production environment.

[edx-pipeline-bot]

2U Release Notice: This PR has been rolled back from the edX production environment.

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX production environment.

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX production environment.