Dartium support for manual custom element upgrades.

Source/bindings/dart/DartCustomElementConstructorBuilder.cpp

Index: Source/bindings/dart/DartCustomElementConstructorBuilder.cpp
diff --git a/Source/bindings/dart/DartCustomElementConstructorBuilder.cpp b/Source/bindings/dart/DartCustomElementConstructorBuilder.cpp
index fd4dbf748625b6a55379bebac057aba9ea6a1856..77e04afb97d796ac36fef736659a8f2009f69639 100644
--- a/Source/bindings/dart/DartCustomElementConstructorBuilder.cpp
+++ b/Source/bindings/dart/DartCustomElementConstructorBuilder.cpp
@@ -91,15 +91,14 @@ bool DartCustomElementConstructorBuilder::validateOptions(const AtomicString& ty
 
         m_nativeClassId = reinterpret_cast<intptr_t>(DartDOMWrapper::readNativePointer(nativeElement, DartDOMWrapper::kNativeTypeIndex));
 
-        // TODO: enable once we pick up Blink version 31
-        // if (!Document::isValidName(localName)) {
-        //     CustomElementException::throwException(CustomElementException::ExtendsIsInvalidName, type, es);
-        //     return false;
-        // }
-        // if (CustomElement::isValidName(localName)) {
-        //     CustomElementException::throwException(CustomElementException::ExtendsIsCustomElementName, type, es);
-        //     return false;
-        // }
+        if (!Document::isValidName(localName)) {
+            CustomElementException::throwException(CustomElementException::ExtendsIsInvalidName, type, es);
+            return false;
+        }
+        if (CustomElement::isValidName(localName)) {
+            CustomElementException::throwException(CustomElementException::ExtendsIsCustomElementName, type, es);
+            return false;
+        }
     } else {
         localName = type;
         m_nativeClassId = DartHTMLElement::dartClassId;