Form attributes mishandled by attr() when fields share names with attributes

[kenaniah]

Consider the following form:

  <form id="frm" action="search.html" method="post">
    <input type="hidden" name="action" value="search" /> 
    <input name="term" value="" />
    <input type="submit" value="Search" />
  </form>

One would expect $("#frm").attr('action') to return search.html. Instead, the attribute look up fails. I believe this is because document.getElementById("frm").action returns the <input> element instead of the attribute node. jQuery should instead utilize the form.attributes nodemap to access form attributes, because named form fields are promoted to direct children of the form node and effectively override the attribute nodes when attribute names and field names collide.

[dmethvin]

This is a duplicate of #3113.