Auto merge of #13066 - mskrzypkows:htmlselect_index, r=KiChjang

Implement indexed access on select elements

<!-- Please describe your changes on the following line: -->
Added methods for indexed access on select: SetLength, Length, Item, IndexedGetter

---
<!-- 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 #11763 (github issue number if applicable).

<!-- Either: -->
- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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tests/wpt/metadata/FileAPI/blob/Blob-constructor.html.ini

@@ -16,10 +16,6 @@
     expected: FAIL
     bug: https://github.com/servo/servo/issues/10911
 
-  [Passing an platform object that supports indexed properties as the blobParts array should work (select).]
-    expected: FAIL
-    bug: https://github.com/servo/servo/issues/11763
-
   [Passing a FrozenArray as the blobParts array should work (FrozenArray<MessagePort>).]
     expected: FAIL
     bug: https://github.com/servo/servo/issues/7457

tests/wpt/metadata/html/dom/interfaces.html.ini

@@ -3750,12 +3750,6 @@
   [HTMLSelectElement interface: attribute options]
     expected: FAIL
 
-  [HTMLSelectElement interface: attribute length]
-    expected: FAIL
-
-  [HTMLSelectElement interface: operation item(unsigned long)]
-    expected: FAIL
-
   [HTMLSelectElement interface: operation namedItem(DOMString)]
     expected: FAIL
 
@@ -3801,15 +3795,6 @@
   [HTMLSelectElement interface: document.createElement("select") must inherit property "options" with the proper type (9)]
     expected: FAIL
 
-  [HTMLSelectElement interface: document.createElement("select") must inherit property "length" with the proper type (10)]
-    expected: FAIL
-
-  [HTMLSelectElement interface: document.createElement("select") must inherit property "item" with the proper type (11)]
-    expected: FAIL
-
-  [HTMLSelectElement interface: calling item(unsigned long) on document.createElement("select") with too few arguments must throw TypeError]
-    expected: FAIL
-
   [HTMLSelectElement interface: document.createElement("select") must inherit property "namedItem" with the proper type (12)]
     expected: FAIL
 
@@ -10679,4 +10664,3 @@
 
   [Navigator interface: window.navigator must inherit property "hardwareConcurrency" with the proper type (22)]
     expected: FAIL
-

tests/wpt/metadata/html/semantics/forms/the-select-element/common-HTMLOptionsCollection.html.ini

@@ -1,18 +0,0 @@
-[common-HTMLOptionsCollection.html]
-  type: testharness
-  [On getting, the length attribute must return the number of nodes represented by the collection.]
-    expected: FAIL
-    bug: https://github.com/servo/servo/issues/11763
-
-  [Changing the length adds new nodes; The number of new nodes = new length minus old length]
-    expected: FAIL
-    bug: https://github.com/servo/servo/issues/11763
-
-  [New nodes have no value]
-    expected: FAIL
-    bug: https://github.com/servo/servo/issues/11763
-
-  [Setting a length equal to existing length changes nothing]
-    expected: FAIL
-    bug: https://github.com/servo/servo/issues/11763
-