PROTON-2448: Fix the frame trace not to dump null fields in described lists
PROTON-2448: Fix the frame trace not to dump null fields in described lists

gemmellr/qpid-proton,apache/qpid-proton,astitcher/qpid-proton,apache/qpid-proton,astitcher/qpid-proton,apache/qpid-proton,astitcher/qpid-proton,gemmellr/qpid-proton,gemmellr/qpid-proton,astitcher/qpid-proton,astitcher/qpid-proton,apache/qpid-proton,gemmellr/qpid-proton,gemmellr/qpid-proton,gemmellr/qpid-proton,astitcher/qpid-proton,apache/qpid-proton,apache/qpid-proton