Implemented the SMTO_ABORTIFHUNG flag of SendMessageTimeout.

diff --git a/server/trace.c b/server/trace.c
index 58cec6b..5c7970c 100644
--- a/server/trace.c
+++ b/server/trace.c
@@ -1834,6 +1834,7 @@
 {
     fprintf( stderr, " id=%04x,", req->id );
     fprintf( stderr, " type=%d,", req->type );
+    fprintf( stderr, " flags=%d,", req->flags );
     fprintf( stderr, " win=%p,", req->win );
     fprintf( stderr, " msg=%08x,", req->msg );
     fprintf( stderr, " wparam=%08x,", req->wparam );