dirstate-item: drop the legacy new_added constructor
Nobody is calling it anymore. Its purposes has been filled.
Differential Revision: https://phab.mercurial-scm.org/D11601
{header}
<title>Error</title>
<description>Error</description>
<item>
<title>Error</title>
<description>{error|escape}</description>
<guid>https://mercurial-scm.org/#error</guid>
</item>
</channel>
</rss>