Revert "Dartium JS Interop enabled."

tools/dom/src/Html5NodeValidator.dart

 // DO NOT EDIT- this file is generated from running tool/generator.sh.
 
 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.dom.html;
 
 /**
  * A Dart DOM validator generated from Caja whitelists.
@@ skipping 405 matching lines @@
         _attributeValidators[attr] = _standardAttributeValidator;
       }
 
       for (var attr in _uriAttributes) {
         _attributeValidators[attr] = _uriAttributeValidator;
       }
     }
   }
 
   bool allowsElement(Element element) {
-    return _allowedElements.contains(element._safeTagName);
+    return _allowedElements.contains(element.tagName);
   }
 
   bool allowsAttribute(Element element, String attributeName, String value) {
-    var tagName = element._safeTagName;
+    var tagName = element.tagName;
     var validator = _attributeValidators['$tagName::$attributeName'];
     if (validator == null) {
       validator = _attributeValidators['*::$attributeName'];
     }
     if (validator == null) {
       return false;
     }
     return validator(element, attributeName, value, this);
   }
 
   static bool _standardAttributeValidator(Element element, String attributeName,
       String value, _Html5NodeValidator context) {
     return true;
   }
 
   static bool _uriAttributeValidator(Element element, String attributeName,
       String value, _Html5NodeValidator context) {
     return context.uriPolicy.allowsUri(value);
   }
 }