kmswebrtcendpoint: Fix wrong management of errors
kmswebrtcendpoint: Fix wrong management of errors

Change-Id: I604a6dddf2d1ee174b5fe388da807a15a0e4a4f8

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