Adding untrusted crash dump / stack trace tests.

src/trusted/service_runtime/sel_main.c

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * NaCl Simple/secure ELF loader (NaCl SEL).
  */
 #include "native_client/src/include/portability.h"
@@ skipping 374 matching lines @@
           NaClLog(LOG_FATAL, "Adding item to env_vars failed\n");
         }
         break;
       default:
         fprintf(stderr, "ERROR: unknown option: [%c]\n\n", opt);
         PrintUsage();
         exit(-1);
     }
   }
 
+  if (getenv("NACL_UNTRUSTED_EXCEPTION_HANDLING") != NULL) {
+    exception_handling_requested = 1;
+  }
   if (exception_handling_requested) {
 #if NACL_WINDOWS
     int status;
     DWORD exit_code;
     enable_exception_handling = 1;
     status = NaClLaunchAndDebugItself(argv[0], &exit_code);
     if (status == DEBUG_EXCEPTION_HANDLER_NOT_SUPPORTED) {
       enable_exception_handling = 0;
     } else if (status == DEBUG_EXCEPTION_HANDLER_SUCCESS) {
       return exit_code;
@@ skipping 524 matching lines @@
   fflush(stdout);
 
   if (handle_signals) NaClSignalHandlerFini();
   NaClAllModulesFini();
 
   NaClExit(ret_code);
 
   /* Unreachable, but having the return prevents a compiler error. */
   return ret_code;
 }