Get rid of assumptions about ".nexe" extension.

tests/app_lib/nacl.scons

 # -*- python -*-
 # Copyright 2008 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.
 
 
 Import('env')
 
 ######################################################################
 # Smoke Test
 ######################################################################
-env.ComponentProgram('app_lib_test.nexe',
-                     'app_lib_test.c',
-                     EXTRA_LIBS=['pthread'],
-                     )
+nexe = env.ComponentProgram('app_lib_test',
+                            'app_lib_test.c',
+                            EXTRA_LIBS=['pthread'],
+                            )
 
 # NOTE: we are using the same file as stdin and on the command line
 #
 # app_lib_test exercises stdio, in particular, it uses fopen on the
 # command line argument, so it requires the -a flag to sel_ldr in
 # order to access the filesystem.
 node = env.CommandSelLdrTestNacl(
      'app_lib_test.out',
-     command=[env.File('app_lib_test.nexe'), env.File('app_lib_test.stdin')],
+     nexe,
+     args=[env.File('app_lib_test.stdin')],
      stdin=env.File('app_lib_test.stdin'),
      stdout_golden=env.File('app_lib_test.stdout'),
      sel_ldr_flags=['-a'],
      )
 
 env.AddNodeToTestSuite(node, ['small_tests'], 'run_app_lib_test')