Drop checkedDowncast<>() casting function

[cdumez]

23199ac

Drop checkedDowncast<>() casting function
https://bugs.webkit.org/show_bug.cgi?id=271767

Reviewed by Anne van Kesteren.

Drop checkedDowncast<>() casting function, now that downcast<>() has become
equivalent (as safe).

* Source/WTF/wtf/Ref.h:
(WTF::checkedDowncast): Deleted.
* Source/WTF/wtf/RefPtr.h:
(WTF::checkedDowncast): Deleted.
* Source/WTF/wtf/TypeCasts.h:
(WTF::checkedDowncast): Deleted.
* Source/WebCore/accessibility/AXCoreObject.h:
(WebCore::Accessibility::findChild):
* Source/WebCore/accessibility/AXObjectCache.cpp:
(WebCore::AXObjectCache::handleTextChanged):
* Source/WebCore/accessibility/isolatedtree/AXIsolatedTree.cpp:
(WebCore::AXIsolatedTree::updateDependentProperties):
* Source/WebCore/animation/WebAnimationUtilities.cpp:
(WebCore::compareStyleOriginatedAnimationEvents):
* Source/WebCore/css/typedom/StylePropertyMap.cpp:
(WebCore::StylePropertyMap::set):
* Source/WebCore/dom/DataTransfer.cpp:
(WebCore::DataTransfer::setDataFromItemList):
* Source/WebCore/dom/Document.cpp:
(WebCore::Document::enqueueOverflowEvent):
* Source/WebCore/dom/Element.cpp:
(WebCore::Element::cloneShadowTreeIfPossible):
(WebCore::Node::setCustomElementState):
(WebCore::Element::ensureFormAssociatedCustomElement):
* Source/WebCore/dom/TreeScope.cpp:
(WebCore::TreeScope::ref const):
(WebCore::TreeScope::deref const):
(WebCore::TreeScope::registerCheckedPtr const):
(WebCore::TreeScope::copyCheckedPtr const):
(WebCore::TreeScope::moveCheckedPtr const):
(WebCore::TreeScope::unregisterCheckedPtr const):
* Source/WebCore/html/AttachmentAssociatedElement.cpp:
(WebCore::AttachmentAssociatedElement::cloneAttachmentAssociatedElementWithoutAttributesAndChildren):
* Source/WebCore/html/HTMLCanvasElement.cpp:
(WebCore::HTMLCanvasElement::getContext):
* Source/WebCore/html/HTMLImageElement.cpp:
(WebCore::HTMLImageElement::copyNonAttributePropertiesFromElement):
* Source/WebCore/html/HTMLInputElement.cpp:
(WebCore::HTMLInputElement::switchAnimationVisuallyOnProgress const):
(WebCore::HTMLInputElement::isSwitchVisuallyOn const):
(WebCore::HTMLInputElement::switchAnimationPressedProgress const):
* Source/WebCore/html/HTMLSourceElement.cpp:
(WebCore::HTMLSourceElement::copyNonAttributePropertiesFromElement):
* Source/WebCore/html/canvas/GPUCanvasContextCocoa.mm:
(WebCore::GPUCanvasContextCocoa::htmlOrOffscreenCanvas const):
* Source/WebCore/html/parser/HTMLConstructionSite.cpp:
(WebCore::HTMLConstructionSite::insertHTMLTemplateElement):
* Source/WebCore/html/parser/HTMLTreeBuilder.cpp:
(WebCore::HTMLTreeBuilder::processTemplateEndTag):
* Source/WebCore/html/shadow/DateTimeEditElement.cpp:
(WebCore::DateTimeEditElement::fieldsWrapperElement const):
* Source/WebCore/html/shadow/DateTimeFieldElement.cpp:
(WebCore::DateTimeFieldElement::updateVisibleValue):
* Source/WebCore/html/shadow/DetailsMarkerControl.cpp:
(WebCore::DetailsMarkerControl::rendererIsNeeded):
* Source/WebCore/html/shadow/ProgressShadowElement.cpp:
(WebCore::ProgressShadowElement::progressElement const):
* Source/WebCore/html/shadow/SliderThumbElement.cpp:
(WebCore::RenderSliderContainer::computeLogicalHeight const):
(WebCore::RenderSliderContainer::layout):
(WebCore::SliderThumbElement::hostInput const):
* Source/WebCore/html/shadow/TextControlInnerElements.cpp:
(WebCore::TextControlInnerTextElement::renderer const):
(WebCore::TextControlInnerTextElement::resolveCustomStyle):
(WebCore::TextControlPlaceholderElement::resolveCustomStyle):
(WebCore::SearchFieldResultsButtonElement::defaultEventHandler):
(WebCore::SearchFieldCancelButtonElement::resolveCustomStyle):
(WebCore::SearchFieldCancelButtonElement::defaultEventHandler):
(WebCore::SearchFieldCancelButtonElement::willRespondToMouseClickEventsWithEditability const):
* Source/WebCore/page/FocusController.cpp:
(WebCore::FocusNavigationScope::owner const):
* Source/WebCore/rendering/LegacyLineLayout.cpp:
(WebCore::LegacyLineLayout::createLineBoxes):
* Source/WebCore/rendering/RenderBox.cpp:
(WebCore::RenderBox::computeReplacedLogicalHeightUsing const):
* Source/WebCore/rendering/RenderTheme.cpp:
(WebCore::updateSwitchThumbPartForRenderer):
(WebCore::updateSwitchTrackPartForRenderer):
* Source/WebCore/rendering/svg/SVGResourcesCache.cpp:
(WebCore::SVGResourcesCache::resourceDestroyed):
* Source/WebKit/WebProcess/WebPage/ios/WebPageIOS.mm:
(WebKit::WebPage::removeTextPlaceholder):

Canonical link: https://commits.webkit.org/276778@main

1327eac

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-skia
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 tv-sim		✅ 🧪 api-gtk
	✅ 🛠 watch		✅ 🛠 jsc-armv7
✅ 🛠 🧪 unsafe-merge	✅ 🛠 watch-sim		✅ 🧪 jsc-armv7-tests

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 8426de1)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	🛠 ios	🛠 mac	🛠 wpe	🛠 wincairo
✅ 🧪 bindings	🛠 ios-sim	🛠 mac-AS-debug	🧪 wpe-wk2
✅ 🧪 webkitperl	🧪 ios-wk2	🧪 api-mac	🧪 api-wpe
	🧪 ios-wk2-wpt	🧪 mac-wk1	🛠 wpe-skia
✅ 🛠 🧪 jsc	🧪 api-ios	🧪 mac-wk2	🛠 gtk
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv	🧪 mac-AS-debug-wk2	🧪 gtk-wk2
	✅ 🛠 tv-sim	🧪 mac-wk2-stress	🧪 api-gtk
	✅ 🛠 watch		🛠 jsc-armv7
	✅ 🛠 watch-sim		🧪 jsc-armv7-tests

[webkit-early-warning-system]

EWS run on current version of this PR (hash 1327eac)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	✅ 🛠 wpe-skia
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 tv-sim		✅ 🧪 api-gtk
	✅ 🛠 watch		✅ 🛠 jsc-armv7
✅ 🛠 🧪 unsafe-merge	✅ 🛠 watch-sim		✅ 🧪 jsc-armv7-tests

[webkit-commit-queue]

Committed 276778@main (23199ac): https://commits.webkit.org/276778@main

Reviewed commits have been landed. Closing PR #26518 and removing active labels.