allow passing null to reset blob fields (task #6433)
allow passing null to reset blob fields (task #6433)

QoboLtd/project-template-cakephp,QoboLtd/project-template-cakephp,QoboLtd/project-template-cakephp,QoboLtd/project-template-cakephp,QoboLtd/project-template-cakephp