This also merges pull request #8290 plus a few other fixes from
@ambrop72 and me.
The summary of changes is:
* Update all channels to latest upstream.
* Update GYP package and drop gyp_svn1977.
* Remove ICU from buildInputs to prevent build failure.
* Switch back to using --depth . to GYP instead of patching in the
absolute store paths.
* Don't symlink source code anymore, which might introduce a
regression on high I/O load on Hydra. As this is only a temporary
build fix, let's cross fingers and hope we don't hit it. See
c92dbffeac for an explanation.
* Use HTTPS for the bucket URL.
* Fix nix_plugin_paths patch for version 44 and higher.
Tested at: https://headcounter.org/hydra/eval/169134