Currently the child process summary lines are indistinguishable from the
main process one. This makes it impossible to automatically detect
when a process exits abruptly, i.e. without printing a summary line,
if it has run a subprocess.

This will let analysis tools identify which summary lines correspond to
processes they started and thus when some are missing.  Note also that
in case of a crash the 'unhandled exception' play the same role as the
test summary lines. Thus it is important to also tag them with the pid
of the source process.
Signed-off-by: Francois Gouget <fgouget@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>