PUBDEV-977 Fix POJO preview collapse/expand
PUBDEV-977 Fix POJO preview collapse/expand

junwucs/h2o-flow,printedheart/h2o-flow,nilbody/h2o-flow,printedheart/h2o-flow,nilbody/h2o-flow,h2oai/h2o-flow,junwucs/h2o-flow,junwucs/h2o-flow,h2oai/h2o-flow,printedheart/h2o-flow,nilbody/h2o-flow