LibWeb: Make factory method of HTML::DOMStringMap fallible

Userland/Libraries/LibWeb/HTML/DOMStringMap.cpp

@@ -12,10 +12,10 @@
 
 namespace Web::HTML {
 
-JS::NonnullGCPtr<DOMStringMap> DOMStringMap::create(DOM::Element& element)
+WebIDL::ExceptionOr<JS::NonnullGCPtr<DOMStringMap>> DOMStringMap::create(DOM::Element& element)
 {
     auto& realm = element.realm();
-    return realm.heap().allocate<DOMStringMap>(realm, element).release_allocated_value_but_fixme_should_propagate_errors();
+    return MUST_OR_THROW_OOM(realm.heap().allocate<DOMStringMap>(realm, element));
 }
 
 DOMStringMap::DOMStringMap(DOM::Element& element)

Userland/Libraries/LibWeb/HTML/DOMStringMap.h

@@ -17,7 +17,7 @@ class DOMStringMap final : public Bindings::LegacyPlatformObject {
     WEB_PLATFORM_OBJECT(DOMStringMap, Bindings::LegacyPlatformObject);
 
 public:
-    static JS::NonnullGCPtr<DOMStringMap> create(DOM::Element&);
+    static WebIDL::ExceptionOr<JS::NonnullGCPtr<DOMStringMap>> create(DOM::Element&);
 
     virtual ~DOMStringMap() override;
 

Userland/Libraries/LibWeb/HTML/HTMLElement.cpp

@@ -7,6 +7,7 @@
 #include <AK/StringBuilder.h>
 #include <LibJS/Interpreter.h>
 #include <LibWeb/ARIA/Roles.h>
+#include <LibWeb/Bindings/ExceptionOrUtils.h>
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/DOM/IDLEventListener.h>
 #include <LibWeb/DOM/ShadowRoot.h>
@@ -45,7 +46,9 @@ JS::ThrowCompletionOr<void> HTMLElement::initialize(JS::Realm& realm)
     MUST_OR_THROW_OOM(Base::initialize(realm));
     set_prototype(&Bindings::ensure_web_prototype<Bindings::HTMLElementPrototype>(realm, "HTMLElement"));
 
-    m_dataset = DOMStringMap::create(*this);
+    m_dataset = TRY(Bindings::throw_dom_exception_if_needed(realm.vm(), [&]() {
+        return DOMStringMap::create(*this);
+    }));
 
     return {};
 }

Userland/Libraries/LibWeb/SVG/SVGElement.cpp

@@ -12,7 +12,7 @@ namespace Web::SVG {
 
 SVGElement::SVGElement(DOM::Document& document, DOM::QualifiedName qualified_name)
     : Element(document, move(qualified_name))
-    , m_dataset(HTML::DOMStringMap::create(*this))
+    , m_dataset(HTML::DOMStringMap::create(*this).release_value_but_fixme_should_propagate_errors())
 {
 }