Remove ENABLE_CUSTOM_ELEMENTS compile time flag

Source/core/dom/Document.cpp

Index: Source/core/dom/Document.cpp
diff --git a/Source/core/dom/Document.cpp b/Source/core/dom/Document.cpp
index 3ff02559674a20da7bbb81f51bd9c284da25e06c..8d93c70284f5d62299089d7f59b032e6a471a646 100644
--- a/Source/core/dom/Document.cpp
+++ b/Source/core/dom/Document.cpp
@@ -636,9 +636,7 @@ void Document::dispose()
 
     detachParser();
 
-#if ENABLE(CUSTOM_ELEMENTS)
     m_registry.clear();
-#endif
 
     // removeDetachedChildren() doesn't always unregister IDs,
     // so tear down scope information upfront to avoid having stale references in the map.
@@ -790,7 +788,6 @@ PassRefPtr<Element> Document::createElement(const AtomicString& name, ExceptionC
     return createElement(QualifiedName(nullAtom, name, nullAtom), false);
 }
 
-#if ENABLE(CUSTOM_ELEMENTS)
 PassRefPtr<Element> Document::createElement(const AtomicString& localName, const AtomicString& typeExtension, ExceptionCode& ec)
 {
     if (!isValidName(localName)) {
@@ -849,7 +846,6 @@ void Document::didCreateCustomElement(Element* element, CustomElementConstructor
     if (m_registry)
         m_registry->didCreateElement(element);
 }
-#endif // ENABLE(CUSTOM_ELEMENTS)
 
 PassRefPtr<DocumentFragment> Document::createDocumentFragment()
 {