fixed potential crash in traf merging when packed samples are used
fixed potential crash in traf merging when packed samples are used

RodolpheFouquet/gpac,rbouqueau/gpac,rbouqueau/gpac,gpac/gpac,gpac/gpac,gpac/gpac,rbouqueau/gpac,rbouqueau/gpac,RodolpheFouquet/gpac,RodolpheFouquet/gpac,gpac/gpac,RodolpheFouquet/gpac,rbouqueau/gpac,gpac/gpac,RodolpheFouquet/gpac,RodolpheFouquet/gpac,rbouqueau/gpac,gpac/gpac,gpac/gpac,rbouqueau/gpac,gpac/gpac,rbouqueau/gpac