sample_event.c: Synchronize with master
sample_event.c: Synchronize with master

Previous merger seems didn't do properly. There are some changes in the master didn't make to this branch

HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit,HPCToolkit/hpctoolkit