Revert "Converting Polymer and TemplateElement to use deprecated Node.document"

tools/dom/templates/html/impl/impl_HTMLTemplateElement.darttemplate

Index: tools/dom/templates/html/impl/impl_HTMLTemplateElement.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_HTMLTemplateElement.darttemplate b/tools/dom/templates/html/impl/impl_HTMLTemplateElement.darttemplate
index 1ba903c8d3615d54d823262a92587b929ed2c29f..4a7c784bed3d6981bfc53d863aa0e3a813cdc28a 100644
--- a/tools/dom/templates/html/impl/impl_HTMLTemplateElement.darttemplate
+++ b/tools/dom/templates/html/impl/impl_HTMLTemplateElement.darttemplate
@@ -152,7 +152,7 @@ $!MEMBERS
      }
 
     if (!isNative) {
-      var doc = _getTemplateContentsOwner(templateElement.document);
+      var doc = _getTemplateContentsOwner(templateElement.ownerDocument);
       templateElement._templateContent = doc.createDocumentFragment();
     }
 
@@ -201,7 +201,7 @@ $!MEMBERS
   //       + <td>Bar</td>
   //
   static Element _extractTemplateFromAttributeTemplate(Element el) {
-    var template = el.document.createElement('template');
+    var template = el.ownerDocument.createElement('template');
     el.parentNode.insertBefore(template, el);
 
     for (var name in el.attributes.keys.toList()) {