Fix for input/datalist failure when datalist is created outside document

Source/core/html/HTMLInputElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2007 Samuel Weinig (sam@webkit.org)
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2012 Samsung Electronics. All rights reserved.
@@ skipping 1420 matching lines @@
             argv.append("input");
             argv.append(fastGetAttribute(typeAttr));
             argv.append(fastGetAttribute(formactionAttr));
             activityLogger->logEvent("blinkAddElement", argv.size(), argv.data());
         }
     }
     HTMLTextFormControlElement::insertedInto(insertionPoint);
     if (insertionPoint->inDocument() && !form())
         addToRadioButtonGroup();
     resetListAttributeTargetObserver();
-    return InsertionDone;
+    return InsertionShouldCallDidNotifySubtreeInsertions;
 }
 
 void HTMLInputElement::removedFrom(ContainerNode* insertionPoint)
 {
     if (insertionPoint->inDocument() && !form())
         removeFromRadioButtonGroup();
     HTMLTextFormControlElement::removedFrom(insertionPoint);
     ASSERT(!inDocument());
     resetListAttributeTargetObserver();
 }
@@ skipping 427 matching lines @@
 {
     return m_inputTypeView->customStyleForRenderer(originalStyleForRenderer());
 }
 #endif
 
 bool HTMLInputElement::shouldDispatchFormControlChangeEvent(String& oldValue, String& newValue)
 {
     return m_inputType->shouldDispatchFormControlChangeEvent(oldValue, newValue);
 }
 
+void HTMLInputElement::didNotifySubtreeInsertionsToDocument()
+{
+    listAttributeTargetChanged();
+}
+
 } // namespace