An xsl:choose with a single xsl:when and no xsl:otherwise is just an
xsl:if. Use the simpler xsl:if instead. A choose that also has an
xsl:otherwise is a genuine if/else and is left alone, and a choose with no
xsl:when at all is reported by empty-choose, not here.
Incorrect:
<xsl:choose>
<xsl:when test="@active">Active</xsl:when>
</xsl:choose>
Correct:
<xsl:if test="@active">Active</xsl:if>