Fixing a number of dart:html analyzer issues

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

 // Copyright (c) 2012, 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 $LIBRARYNAME;
 
 // TODO(jacobr): use _Lists.dart to remove some of the duplicated
 // functionality.
 class _ChildrenElementList implements List {
   // Raw Element.
@@ skipping 1043 matching lines @@
    * <http://msdn.microsoft.com/en-us/library/ie/ms532998(v=vs.85).aspx>.
    */
   static Element _createTableForIE(String html, String tag) {
     var div = new Element.tag('div');
     div.innerHtml = '<table>$html</table>';
     var table = _singleNode(div.children);
     Element element;
     switch (tag) {
       case 'td':
       case 'th':
-        element = _singleNode(_singleNode(table.rows).cells);
+        TableRowElement row = _singleNode(table.rows);
+        element = _singleNode(row.cells);
         break;
       case 'tr':
         element = _singleNode(table.rows);
         break;
       case 'tbody':
         element = _singleNode(table.tBodies);
         break;
       case 'thead':
         element = table.tHead;
         break;
@@ skipping 48 matching lines @@
   const ScrollAlignment._internal(this._value);
   toString() => 'ScrollAlignment.$_value';
 
   /// Attempt to align the element to the top of the scrollable area.
   static const TOP = const ScrollAlignment._internal('TOP');
   /// Attempt to center the element in the scrollable area.
   static const CENTER = const ScrollAlignment._internal('CENTER');
   /// Attempt to align the element to the bottom of the scrollable area.
   static const BOTTOM = const ScrollAlignment._internal('BOTTOM');
 }