(cherry picked from commit 8eb2551)

https://chromereleases.googleblog.com/2020/12/stable-channel-update-for-desktop.html

This update includes 0 security fixes.

(cherry picked from commit 36d40f7)

(cherry picked from commit beb8359)

(cherry picked from commit f4419dd)

I just regenerated upstream-info.json using update.py again and got a
different hash this time (but the same hash as in NixOS#106272). Therefore,
the only possible explanation I have is that upstream changed the file
that is hosted at [0]. I'll try to contact upstream regarding this.

Fix NixOS#106272.

[0]: https://chromedriver.storage.googleapis.com/87.0.4280.88/chromedriver_linux64.zip

(cherry picked from commit d35b635)

I used nix-instantiate to verify that the derivations for chromium and
ungoogled-chromium remain unchanged (only the meta attributes change
slightly as I added myself as ungoogled-chromium to receive
notifications for PRs/issues).

(cherry picked from commit 2b6b434)

This also adds a dedicated channel for ungoogled-chromium that enables
us to update ungoogled-chromium independently of chromium.
TODO: Automate ungoogled-chromium updates via update.py (currently it
needs to be updated manually).

Note: Unfortunately this changes the ungoogled-chromium derivation
because common.nix passes the channel as an argument to
stdenv.mkDerivation (this makes it more difficult to verify this commit
but the result should remain the same).

(cherry picked from commit 240a8f7)

(cherry picked from commit 4ea2b21)

(cherry picked from commit 397a5ee)

(cherry picked from commit 39c5d11)

(cherry picked from commit 40199cd)

This should fix a regression from NixOS#106475 (hopefully this is the only
issue, my current implementation with channel+ungoogled isn't ideal):
NixOS#106475 (comment)

(cherry picked from commit be94a4c)

(cherry picked from commit 9b846b9)

(cherry picked from commit 94bee10)

Building with Google's proprietary Widevine DRM technology requires
fetching the Google Chrome sources.

(cherry picked from commit 86ff1e4)

Error:
../../components/viz/service/display_embedder/output_presenter_x11.cc:8:10:
fatal error: 'X11/xshmfence.h' file not found
         ^~~~~~~~~~~~~~~~~
1 error generated.

(cherry picked from commit 351f3c0)