How to use literal HTML in eZ Platform

ezpublish.yml

## Path can point wherever, this currently assumes that you're whacking everything in /ezpublish/
##  but really this should be in a bundle.
system:
    some_siteaccess_name:
        fieldtypes:
            ezxml:
                custom_tags: [{path: %kernel.root_dir%/Resources/views/fields/ezxml/fields.xsl}]

fields.xsl

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet
        version="1.0"
        xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
        xmlns:xhtml="http://ez.no/namespaces/ezpublish3/xhtml/"
        xmlns:custom="http://ez.no/namespaces/ezpublish3/custom/"
        xmlns:image="http://ez.no/namespaces/ezpublish3/image/"
        exclude-result-prefixes="xhtml custom image">

    <xsl:output method="html" indent="yes" encoding="UTF-8"/>

    <!-- Literal HTML -->
    <xsl:template match="literal">
        <xsl:choose>
            <xsl:when test="@class='html'">
                <xsl:value-of select="." disable-output-escaping="yes"/>
            </xsl:when>
            <xsl:otherwise>
                <pre>
                    <xsl:copy-of select="@*"/>
                    <xsl:apply-templates/>
                </pre>
            </xsl:otherwise>
        </xsl:choose>
    </xsl:template>

</xsl:stylesheet>