This PR is the run of `gn format` on all `gn` files. This is a mechanical change done with: ```sh git ls-files -- "*.gn" | xargs gn format git ls-files -- "*.gni" | xargs gn format ``` This change has been motivated primarily by an improvement to the formatters privided by `gn` correcting cases of redundant target naming, i.e cases where `//foo:foo` is used, and should just be `//foo`. For this particular `gn` change, see: https://chromium.googlesource.com/chromium/src/+/c822490a82cdb6ad479159683a92858f7c6f0a58 Resolves https://github.com/brave/brave-browser/issues/48161