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Moved the `pub_domains` module from `net` into `net_traits`, so it can be used by crates which don't depend on `net` (in particular `constellation`, which can use the crate for testing similar-origin).
I also did quite a bit of tidying up, the functions now do no heap allocation, previously there was quite a bit of String allocation going on.
This is the next step to fixing #633. cc @jdm
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] There are tests for these changes (new unit tests)
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Source-Repo: https://github.com/servo/servo
Source-Revision: 128a61eb9d7a7dbb3ad8bdd9218efcc171229c61
cd436f3587