Fix OMPT state maintenance for barriers and missing init of implicit task id.

Fix OMPT state maintenance for barriers and missing init of implicit task id.

Fix OMPT support for barriers so that state changes occur even if OMPT_TRACE turned off.
These state changes are needed by performance tools that use callbacks for either
ompt_event_wait_barrier_begin or ompt_event_wait_barrier_end.  Change ifdef flag to OMPT_BLAME
for callbacks ompt_event_wait_barrier_begin or ompt_event_wait_barrier_end rather than
OMPT_TRACE -- they were misclassified.  Without this patch, when the runtime is compiled with
LIBOMP_OMPT_SUPPORT=true, LIBOMP_OMPT_BLAME=true, and LIBOMP_OMPT_TRACE=false, and a callback
is registered for either ompt_event_wait_barrier_begin or ompt_event_wait_barrier_end, then an
assertion will trip.  Fix the scoping of one OMPT_TRACE ifdef, which should not have surrounded
an update of an OMPT state.  Add a missing initialization of an OMPT task id for an implicit task.

Patch by John Mellor-Crummey

Differential Revision: http://reviews.llvm.org/D10759

llvm-svn: 240970