Make arguments to Range methods non-optional

LayoutTests/editing/deleting/delete-uneditable-style.html

 <script src="../../resources/dump-as-markup.js"></script>
 <div contentEditable id="test">
   <span id="start">start</span>
   editable-1
   <div contentEditable="false">
     <style>#end { color: red; }</style>
     <link type="foo" href="bar">
     uneditable
   </div>
   editable-2
 <span id="end">end</span>
 </div>
 <script>
 Markup.description('Test case for crash bug http://crbug.com/177470');
 function $(id) { return document.getElementById(id); }
 var range = document.createRange();
-range.setStart($('start'));
+range.setStart($('start'), 0);
 range.setEnd($('end'), NaN);
 getSelection().addRange(range);
 document.execCommand('delete', null, '');
 Markup.dump($('test'));
 </script>