Report exit status in debug stub, if tab is closed in chrome.

src/trusted/service_runtime/nacl_secure_service.c

Index: src/trusted/service_runtime/nacl_secure_service.c
===================================================================
--- src/trusted/service_runtime/nacl_secure_service.c	(revision 10072)
+++ src/trusted/service_runtime/nacl_secure_service.c	(working copy)
@@ -101,7 +101,13 @@
   }
   if (0 == --self->conn_count) {
     NaClLog(4, "NaClSecureServiceThread: all channels closed, exiting.\n");
-    NaClExit(0);
+    /*
+     * Set exit code for application.  This wakes up main thread and
+     * application will terminate gracefully there.  This is needed to allow
+     * debug stub to send exit status to debugger.  This way we can detect
+     * normal NaCl module exit in tests.
+     */
+    NaClReportExitStatus(self->nap, 0);
   }
   NaClXMutexUnlock(&self->mu);
 }