servo: Merge #15536 - Implement setter for document.domain (from asajeffrey:script-document-domain-setter); r=nox

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This PR implements the setter for `document.domain`.

It builds on #15438 and #15478, only the last commit is part of this PR.

It includes tests for similar-origin security checks.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #934.
- [X] There are tests for these changes.

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Source-Repo: https://github.com/servo/servo
Source-Revision: e600e0495ce4ab0f1bb798689f8ebeab84258ec3

servo/components/url/lib.rs

@@ -28,6 +28,8 @@ use std::path::Path;
 use std::sync::Arc;
 use url::{Url, Position};
 
+pub use url::Host;
+
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
 pub struct ServoUrl(Arc<Url>);