* src/jmt.c (build_trace): allow passing in a NULL item
* src/jmt.c (build_trace): allow passing in a NULL item

lutter/augeas,manandbytes/augeas,ptoscano/augeas,jasperla/augeas,kumy/augeas,kunkku/augeas,mchf/augeas,GeoffWilliams/augeas,ptoscano/augeas,domcleal/augeas,mchf/augeas,jjlin/augeas,lutter/augeas,pevalme/augeas,ptoscano/augeas,raphink/augeas,raphink/augeas,kumy/augeas,lutter/augeas,hercules-team/augeas-do-not-use,manandbytes/augeas,jjlin/augeas,dafugg/augeas,kumy/augeas,kunkku/augeas,pevalme/augeas,MikaelSmith/augeas,domcleal/augeas,hercules-team/augeas-do-not-use,dafugg/augeas,jtopjian/augeas,MikaelSmith/augeas,hercules-team/augeas,GeoffWilliams/augeas,mlichvar/augeas,domcleal/augeas,hercules-team/augeas-do-not-use,jtopjian/augeas,pevalme/augeas,jjlin/augeas,jasperla/augeas,kunkku/augeas,hercules-team/augeas,kumy/augeas,mlichvar/augeas,mlichvar/augeas,dafugg/augeas