Do not filter out id on some fields #235

As reported in the issue, debugging indicated that filtering the IDs of some
fields in array constructs (in the XSLT M4 supermodel intermediate format) are
dropping in later stages as a result, lead to invalid JSON serialization.

toolchains/xslt-M4/converter-gen/supermodel-to-json.xsl

@@ -138,7 +138,6 @@
         <xsl:element name="{(@in-json[matches(.,'\S')],'string')[1]}"
             namespace="http://www.w3.org/2005/xpath-functions">
             <!-- emit a key only if needed -->
-            <xsl:if test="exists(parent::field/child::flag) or exists(parent::field/parent::assembly) or count(parent::field/parent::group[@in-json='SINGLETON_OR_ARRAY']/child::*) eq 1">
                 <xsl:copy-of
                     select="((../flag[@key = $key-flag-name], parent::field[@in-json = 'SCALAR'])/@key, @key)[1]"/>
                 <!-- overriding the key           -->
@@ -148,7 +147,6 @@
                             mode="cast-data"/>
                     </xsl:attribute>
                 </xsl:if>
-            </xsl:if>
             <xsl:apply-templates select="." mode="cast-data"/>
         </xsl:element>
     </xsl:template>