Remove unneeded call to stringContains
Remove unneeded call to stringContains

This call does not look like it is necessary, and breaks with the
"strict type" php 7 feature.

sonata-project/SonataMediaBundle,OskarStark/SonataMediaBundle,hug963/SonataMediaBundle,jerome-fix/SonataMediaBundle,jerome-fix/SonataMediaBundle,hug963/SonataMediaBundle,hug963/SonataMediaBundle,OskarStark/SonataMediaBundle,jerome-fix/SonataMediaBundle,jerome-fix/SonataMediaBundle,OskarStark/SonataMediaBundle,hug963/SonataMediaBundle,OskarStark/SonataMediaBundle,hug963/SonataMediaBundle