servo: Merge #19724 - Remove out of date FIXME comments from domimplementation (from hindenbug:19723-remove-fixme-comments); r=metajack

<!-- Please describe your changes on the following line: -->
This removes out of date FIXME comments from `domimplementation.rs`

---
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- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #19723

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because this is a comment cleanup

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Source-Repo: https://github.com/servo/servo
Source-Revision: aa199307c86051e13b17a5feb77722ddcdeed5ce

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 389a0f62b8ec997d1ea665182b2ed38a2ad90665

servo/components/script/dom/domimplementation.rs

@@ -114,7 +114,7 @@ impl DOMImplementationMethods for DOMImplementation {
         }
 
         // Step 6.
-        // FIXME: https://github.com/mozilla/servo/issues/1522
+        // The origin is already set
 
         // Step 7.
         Ok(doc)
@@ -183,7 +183,7 @@ impl DOMImplementationMethods for DOMImplementation {
         }
 
         // Step 8.
-        // FIXME: https://github.com/mozilla/servo/issues/1522
+        // The origin is already set
 
         // Step 9.
         doc