brave-browser: Multiple users reporting that HBO Max is broken, likely due to kVideoPlaybackQuality being disabled

Description

HBO Max no longer plays video. Several users are reporting hitting this issue on Reddit as well as on Brave forums.

Steps to Reproduce

1. Log in to HBO Max on Brave 1.19.54
2. The page asks “Who is watching?”. Click on a user name.
3. The web app loads, lists content to watch. Click on any title.
4. Select any episode of any series/film and click on the play button.
5. The page loads the video viewer with a loading indicator and gets stuck there. An error is logged in the console:

app.js:229 Uncaught (in promise) TypeError: this._htmlVideoElement.getVideoPlaybackQuality is not a function
    at i.<anonymous> (app.js:229)
    at app.js:229
    at Object.next (app.js:229)
    at app.js:229
    at new Promise (<anonymous>)
    at uo (app.js:229)
    at i.getState (app.js:229)
    at l.<anonymous> (app.js:225)
    at app.js:229
    at Object.next (app.js:229)
    at app.js:229
    at new Promise (<anonymous>)
    at uo (app.js:229)
    at l._onPlayerTimerUpdate (app.js:225)
    at i._onTick (app.js:225)
    at i.<anonymous> (app.js:222)

Actual result:

The video never starts playing.

Expected result:

Entertaining content.

Reproduces how often:

Always.

Brave version (brave://version info)

Reproduced on Version 1.19.54 Chromium: 87.0.4280.101 (Official Build) beta (64-bit)

Version/Channel Information:

I’ve only tried the beta channel but I suspect this reproduces everywhere.

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? NO
• Does the issue resolve itself when disabling Brave Rewards? NO
• Is the issue reproducible on the latest version of Chrome? NO

Miscellaneous Information:

https://github.com/brave/brave-browser/issues/8029 seems to show that getVideoPlaybackQuality was removed from Brave back in February as a follow-up to Chromium 80 being released. From what I am reading of the stack traced logged on the HBO Max page, it seems like their web app may have started using this API without checking if it’s available. If this is indeed the issue it probably also means that users of Chrome < 80 who haven’t upgraded since February would also be seeing this issue.

The removal in Brave was hardcoded so there is no easy way for me to try turning this feature back on.

/cc @fmarier and @mkarolin who created or are mentioned on the original Brave issue.