Bad merge re-disabled kVideoPlaybackQuality on 1.19.x branch.

[mkarolin]

kVideoPlaybackQuality was removed from disabled features list to fix #13183.

The fix was uplifted to 1.19.x branch by brave/brave-core#7451. However, a later uplift of Chromium 88 changes in brave/brave-core#7518 incorrectly reverted the change.

QA:
Please, retest with the same plan as in the original issue (#13183).

[kjozwiak]

Closing as brave/brave-core#7667 was merged into 1.19.x as per #13679 (reference).

[LaurenWags]

Verified passed with

Brave	1.19.87 Chromium: 88.0.4324.96 (Official Build) (x86_64)
Revision	68dba2d8a0b149a1d3afac56fa74648032bcf46b-refs/branch-heads/4324@{#1784}
OS	macOS Version 10.15.7 (Build 19H15)

Verified test plan from #13183

Installed 1.18.78. Confirmed able to stream HBO Max.
Updated to 1.19.86. Reproduced unable to stream HBO Max.
Updated to 1.19.87. Confirmed able to stream HBO Max.

1.18.78	1.19.86	1.19.87

Also confirmed able to stream HBO Max on clean install of 1.19.87.

---

Verification passed on

Brave | 1.19.87 Chromium: 88.0.4324.96 (Official Build) (64-bit)
-- | --
Revision | 68dba2d8a0b149a1d3afac56fa74648032bcf46b-refs/branch-heads/4324@{#1784}
OS | Windows 10 OS Version 2004 (Build 19041.746)

Clean profile

• ensured able to stream video on hbomax.com in 1.19.87
  

Upgraded _profile_

Reproduced the issue in 1.19.86 - Unable to load the video and getting Uncaught (in promise) TypeError: this._htmlVideoElement.getVideoPlaybackQuality is not a function error in console

Upgraded the profile to 1.1987 and ensured able to stream video on hbomax.com in 1.19.87

---

Verification PASSED on Ubuntu 20.04 x64 using the following build:

Brave | 1.19.87 Chromium: 88.0.4324.96 (Official Build) (64-bit)
--- | ---
Revision | 68dba2d8a0b149a1d3afac56fa74648032bcf46b-refs/branch-heads/4324@{#1784}
OS | Linux

• Installed 1.18.78 and ensured HBO Max was working as expected
• Updated to 1.19.86 and reproduced the original issue re: streaming not working
• Updated to 1.19.87 and ensured HBO Max was working as expected
• Clean installed 1.19.87 and ensured HBO Max was working as expected

1.18.78	1.19.86	1.19.87