<option> label attribute updates are not shown until focus is moved

https://bugs.webkit.org/show_bug.cgi?id=258862

Reviewed by Tim Nguyen.

HTMLOptionElement::label updates from JavaScript were not rendered on parent
<select> element, unless focus was moved to/from it. This change informs the
HTMLSelectElement about <option> child update whenever the label attribute
changes, which allows it to render the updated label.

* LayoutTests/TestExpectations:
* Source/WebCore/html/HTMLOptionElement.cpp:
(WebCore::HTMLOptionElement::attributeChanged):

Canonical link: https://commits.webkit.org/265942@main

LayoutTests/TestExpectations

@@ -824,10 +824,8 @@ imported/w3c/web-platform-tests/html/rendering/the-details-element/details-page-
 imported/w3c/web-platform-tests/html/rendering/the-details-element/details-page-break-after-2-print.html [ ImageOnlyFailure ]
 imported/w3c/web-platform-tests/html/rendering/the-details-element/details-page-break-before-1-print.html [ ImageOnlyFailure ]
 imported/w3c/web-platform-tests/html/rendering/the-details-element/details-page-break-before-2-print.html [ ImageOnlyFailure ]
-imported/w3c/web-platform-tests/html/rendering/widgets/the-select-element/option-add-label.html [ ImageOnlyFailure ]
 imported/w3c/web-platform-tests/html/rendering/widgets/the-select-element/option-empty-label-to-empty-string.html [ ImageOnlyFailure ]
 imported/w3c/web-platform-tests/html/rendering/widgets/the-select-element/option-empty-label.html [ ImageOnlyFailure ]
-imported/w3c/web-platform-tests/html/rendering/widgets/the-select-element/option-rm-label.html [ ImageOnlyFailure ]
 imported/w3c/web-platform-tests/html/semantics/embedded-content/the-iframe-element/iframe-modify-scrolling-attr-to-yes.html [ ImageOnlyFailure ]
 imported/w3c/web-platform-tests/html/semantics/embedded-content/the-img-element/adopt-from-image-document.html [ ImageOnlyFailure ]
 imported/w3c/web-platform-tests/html/semantics/embedded-content/the-img-element/image-loading-lazy-slow-aspect-ratio.html [ ImageOnlyFailure ]

Source/WebCore/html/HTMLOptionElement.cpp

@@ -189,6 +189,11 @@ void HTMLOptionElement::attributeChanged(const QualifiedName& name, const AtomSt
             setSelected(!newValue.isNull());
         break;
     }
+    case AttributeNames::labelAttr: {
+        if (RefPtr select = ownerSelectElement())
+            select->optionElementChildrenChanged();
+        break;
+    }
 #if ENABLE(DATALIST_ELEMENT)
     case AttributeNames::valueAttr:
         for (auto& dataList : ancestorsOfType<HTMLDataListElement>(*this))