Did jQuery drop support to attr on some DOM properties?
<p>I had some old jQuery working code with:</p>

<pre><code>if ($element.attr('checked') === 'checked')
</code></pre>

<p>that was never rewriten to suggested:</p>

<pre><code>if ($element.prop('checked'))
</code></pre>

<p>yet it worked. </p>

<p>But now, I've updated to jQuery 1.9.1 and accessing checked with attr returns undefined. Does it mean that jQuery dropped support for some DOM properties like checked/disabled/selected ? </p>
