HttpEPServer: Do not unref message before using it
HttpEPServer: Do not unref message before using it

Change-Id: I44428bb21e627dd444d7e807a387cdb6e225d27c

shelsonjava/kms-elements,TribeMedia/kms-elements,Kurento/kms-elements,Kurento/kms-elements,shelsonjava/kms-elements,shelsonjava/kms-elements,TribeMedia/kms-elements,TribeMedia/kms-elements,Kurento/kms-elements