Auto merge of #11556 - Manishearth:make-fetch-happen, r=jdm

Make fetch happen

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Moves XHR over to the fetch backend.

Previous PR: https://github.com/servo/servo/pull/114

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- [x] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors (Will fix later)

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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/script/lib.rs

@@ -79,7 +79,6 @@ extern crate style;
 extern crate time;
 #[cfg(any(target_os = "macos", target_os = "linux"))]
 extern crate tinyfiledialogs;
-extern crate unicase;
 extern crate url;
 #[macro_use]
 extern crate util;
@@ -91,7 +90,6 @@ extern crate xml5ever;
 mod blob_url_store;
 pub mod bluetooth_blacklist;
 pub mod clipboard_provider;
-pub mod cors;
 mod devtools;
 pub mod document_loader;
 #[macro_use]