LibWeb: Make factory method of CSS::CSSStyleRule fallible

Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp

@@ -8,12 +8,13 @@
 #include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/CSS/CSSStyleRule.h>
 #include <LibWeb/CSS/Parser/Parser.h>
+#include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::CSS {
 
-CSSStyleRule* CSSStyleRule::create(JS::Realm& realm, NonnullRefPtrVector<Web::CSS::Selector>&& selectors, CSSStyleDeclaration& declaration)
+WebIDL::ExceptionOr<JS::NonnullGCPtr<CSSStyleRule>> CSSStyleRule::create(JS::Realm& realm, NonnullRefPtrVector<Web::CSS::Selector>&& selectors, CSSStyleDeclaration& declaration)
 {
-    return realm.heap().allocate<CSSStyleRule>(realm, realm, move(selectors), declaration).release_allocated_value_but_fixme_should_propagate_errors();
+    return MUST_OR_THROW_OOM(realm.heap().allocate<CSSStyleRule>(realm, realm, move(selectors), declaration));
 }
 
 CSSStyleRule::CSSStyleRule(JS::Realm& realm, NonnullRefPtrVector<Selector>&& selectors, CSSStyleDeclaration& declaration)

Userland/Libraries/LibWeb/CSS/CSSStyleRule.h

@@ -19,7 +19,7 @@ class CSSStyleRule final : public CSSRule {
     WEB_PLATFORM_OBJECT(CSSStyleRule, CSSRule);
 
 public:
-    static CSSStyleRule* create(JS::Realm&, NonnullRefPtrVector<Selector>&&, CSSStyleDeclaration&);
+    static WebIDL::ExceptionOr<JS::NonnullGCPtr<CSSStyleRule>> create(JS::Realm&, NonnullRefPtrVector<Selector>&&, CSSStyleDeclaration&);
 
     virtual ~CSSStyleRule() override = default;
 

Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp

@@ -3120,7 +3120,7 @@ CSSRule* Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
         return {};
     }
 
-    return CSSStyleRule::create(m_context.realm(), move(selectors.value()), *declaration);
+    return CSSStyleRule::create(m_context.realm(), move(selectors.value()), *declaration).release_value_but_fixme_should_propagate_errors();
 }
 
 auto Parser::extract_properties(Vector<DeclarationOrAtRule> const& declarations_and_at_rules) -> PropertiesAndCustomProperties