Auto merge of #25070 - cagandhi:named-form-getter, r=jdm

Named form getter

This PR contains changes related to adding named getter in Servo for getting the list of all meaningful property names for a HTMLFormElement object, and getting the value of a specific property name. The following changes have been made:

* uncomment the [named getter](f63b404e0c/components/script/dom/webidls/HTMLFormElement.webidl (L30)) from HTMLFormElement.webidl
* add the missing `NamedGetter` and `SupportedPropertyNames` methods to [HTMLFormElement](f63b404e0c/components/script/dom/htmlformelement.rs (L113))
* implement `SupportedPropertyNames` according to [the specification](https://html.spec.whatwg.org/multipage/forms.html#the-form-element:supported-property-names):
  * create an enum to represent the `id`, `name`, and `past` states for the sourced names
  * create a vector of `(SourcedName, DomRoot<HTMLElement>)` by iterating over `self.controls` and checking the element type and calling methods like `HTMLElement::is_listed_element`
---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #16479 (GitHub issue number if applicable)

tests/wpt/metadata/html/semantics/forms/form-submission-0/form-double-submit-2.html.ini

@@ -1,5 +1,5 @@
 [form-double-submit-2.html]
-  expected: ERROR
+  expected: TIMEOUT
   [preventDefault should allow onclick submit() to succeed]
     expected: FAIL
 

tests/wpt/metadata/html/semantics/forms/form-submission-0/form-double-submit.html.ini

@@ -1,5 +1,5 @@
 [form-double-submit.html]
-  expected: ERROR
+  expected: TIMEOUT
   [default submit action should supersede onclick submit()]
     expected: FAIL
 

tests/wpt/metadata/html/semantics/forms/form-submission-0/form-submission-algorithm.html.ini

@@ -14,3 +14,6 @@
   [firing an event named submit; form.requestSubmit()]
     expected: FAIL
 
+  [Cannot navigate (after constructing the entry list)]
+    expected: FAIL
+

tests/wpt/metadata/html/semantics/forms/the-fieldset-element/HTMLFieldSetElement.html.ini

@@ -6,6 +6,3 @@
   [The elements must return an HTMLFormControlsCollection object]
     expected: FAIL
 
-  [The controls must root at the fieldset element]
-    expected: FAIL
-

tests/wpt/metadata/html/semantics/forms/the-form-element/form-nameditem.html.ini

@@ -3,33 +3,18 @@
   [Name for a single element should work]
     expected: FAIL
 
-  [Calling item() on the NodeList returned from the named getter should work]
-    expected: FAIL
-
-  [Indexed getter on the NodeList returned from the named getter should work]
-    expected: FAIL
-
   [All listed elements except input type=image should be present in the form]
     expected: FAIL
 
   [Named elements should override builtins]
     expected: FAIL
 
-  [The form attribute should be taken into account for named getters (single element)]
-    expected: FAIL
-
   [The form attribute should be taken into account for named getters (multiple elements)]
     expected: FAIL
 
-  [Input should only be a named property on the innermost form that contains it]
-    expected: FAIL
-
   [Trying to set an expando that would shadow an already-existing named property]
     expected: FAIL
 
-  [Trying to set an expando that shadows a named property that gets added later]
-    expected: FAIL
-
   [Past names map should work correctly]
     expected: FAIL