Auto merge of #11978 - aravind-pg:new-referrer-pols, r=jdm

Add "origin" and "same-origin" referrer policies, replacing "origin-only".

<!-- Please describe your changes on the following line: -->
---
<!-- 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 #11384
- [X] There are tests for these changes

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="35" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/11978)
<!-- Reviewable:end -->

components/net/http_loader.rs

@@ -458,7 +458,8 @@ pub fn determine_request_referrer(headers: &mut Headers,
         let cross_origin = ref_url.origin() != url.origin();
         return match referrer_policy {
             Some(ReferrerPolicy::NoReferrer) => None,
-            Some(ReferrerPolicy::OriginOnly) => strip_url(ref_url, true),
+            Some(ReferrerPolicy::Origin) => strip_url(ref_url, true),
+            Some(ReferrerPolicy::SameOrigin) => if cross_origin { None } else { strip_url(ref_url, false) },
             Some(ReferrerPolicy::UnsafeUrl) => strip_url(ref_url, false),
             Some(ReferrerPolicy::OriginWhenCrossOrigin) => strip_url(ref_url, cross_origin),
             Some(ReferrerPolicy::NoRefWhenDowngrade) | None => no_ref_when_downgrade_header(ref_url, url),