Functional customdb tests fail when nuxeo-test-vcs.properties does not already exist, this is visible on 6.0 and 7.10:
https://qa2.nuxeo.org/jenkins/job/7.10/job/nuxeo-7.10-fullbuild-part1-multidb-linux/Slave=MULTIDB_LINUX_710,dbprofile=mongodb,jdk=java-8-oracle/121/
https://qa2.nuxeo.org/jenkins/job/7.10/job/nuxeo-7.10-fullbuild-part1-multidb-linux/Slave=MULTIDB_LINUX_710,dbprofile=mariadb,jdk=java-8-oracle/121/
https://qa2.nuxeo.org/jenkins/job/6.0/job/nuxeo-6.0-fullbuild-part1-multidb-linux/Slave=MULTIDB_LINUX_710,dbprofile=mongodb,jdk=java-8-oracle/120/console
https://qa2.nuxeo.org/jenkins/job/6.0/job/nuxeo-6.0-fullbuild-part1-multidb-linux/Slave=MULTIDB_LINUX_710,dbprofile=oracle12c,jdk=java-8-oracle/120/console
https://qa2.nuxeo.org/jenkins/job/6.0/job/nuxeo-6.0-fullbuild-part1-multidb-linux/Slave=MULTIDB_LINUX_710,dbprofile=mariadb,jdk=java-8-oracle/120/console