Auto merge of #17224 - cbrewster:html_constructor, r=jdm

WebIDL HTMLConstructor support

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spec: https://html.spec.whatwg.org/multipage/#htmlconstructor

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #17194 (github issue number if applicable).

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

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Cargo.lock

@@ -1372,7 +1372,7 @@ dependencies = [
 [[package]]
 name = "js"
 version = "0.1.6"
-source = "git+https://github.com/servo/rust-mozjs#bc7af508c194d56eef3a2c52772ae261b9a1facb"
+source = "git+https://github.com/servo/rust-mozjs#3de4ff3d52361a47a17e3b4fcb02c779b99d93d4"
 dependencies = [
  "cmake 0.1.22 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",