LTTng.core: Critical Flow fix incorrect process name

LTTng.core: Critical Flow fix incorrect process name

fixes bug 514762

When the task is changing from a task other than idle, it may change its
name, it it is reset to the new name every time as a precaution.

Change-Id: Id65a1861b78de26c9a272b245a7a728f3fc6cca8
Signed-off-by: Abderrahmane Berhil <abdelrahmane.b@gmail.com>
Reviewed-on: https://git.eclipse.org/r/97991
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Reviewed-by: Hudson CI
Reviewed-by: Genevieve Bastien <gbastien+lttng@versatic.net>
Tested-by: Genevieve Bastien <gbastien+lttng@versatic.net>