Check for type registeration of Custom element before validating options

Source/core/dom/custom/CustomElementRegistry.cpp

Index: Source/core/dom/custom/CustomElementRegistry.cpp
diff --git a/Source/core/dom/custom/CustomElementRegistry.cpp b/Source/core/dom/custom/CustomElementRegistry.cpp
index eedbfaa8b750ed1087dcb553b5f9b4099075c27f..a3b9775947ca47e3be8beaadbe578a655a2edc81 100644
--- a/Source/core/dom/custom/CustomElementRegistry.cpp
+++ b/Source/core/dom/custom/CustomElementRegistry.cpp
@@ -81,18 +81,17 @@ CustomElementDefinition* CustomElementRegistry::registerElement(Document* docume
         return 0;
     }
 
+    if (m_registeredTypeNames.contains(type)) {
+        CustomElementException::throwException(CustomElementException::TypeAlreadyRegistered, type, exceptionState);
+        return 0;
+    }
+
     QualifiedName tagName = QualifiedName::null();
     if (!constructorBuilder->validateOptions(type, tagName, exceptionState))
         return 0;
 
     ASSERT(tagName.namespaceURI() == HTMLNames::xhtmlNamespaceURI || tagName.namespaceURI() == SVGNames::svgNamespaceURI);
 
-    // FIXME: This should be done earlier in validateOptions.
-    if (m_registeredTypeNames.contains(type)) {
-        CustomElementException::throwException(CustomElementException::TypeAlreadyRegistered, type, exceptionState);
-        return 0;
-    }
-
     ASSERT(!observer.registrationContextWentAway());
 
     RefPtr<CustomElementLifecycleCallbacks> lifecycleCallbacks = constructorBuilder->createCallbacks();