Use build flag "use_vaapi=true" for Chromium 86+

[xalt7x]

Upstream allowed to enable VAAPI through
chrome://flags/#disable-accelerated-video-decode
Commit URL:
https://chromium-review.googlesource.com/c/chromium/src/+/2208531

But Chromium still needs to be built with flag "use_vaapi=true"

Patch could be easily backported to version 85 but currently Chromium needs to be run with
--use-gl=desktop switch
(I have Bionic build on test PPA https://launchpad.net/~xalt7x/+archive/ubuntu/chromium-deb-vaapi-test-upstream)

Please use this build flag for Snap and Deb builds (16.04 , 18.04) so people with Intel & AMD on X11 wouldn't need to rely 3rd-party PPAs for Hardware acceleration.

Thanks!

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Olivier Tilloy (osomon)]

use_vaapi is enabled by default (on amd64 and i386) starting with chromium 88 (currently dev channel).
snaps in the edge channel already have this, as do the bionic builds in ppa:chromium-team/dev. Chromium depends on a version of libva that's too recent for xenial, so I have disabled it for xenial builds.