Pass command line args to apptests

mojo/tools/apptest_runner.py

 #!/usr/bin/env python
 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """A test runner for gtest application tests."""
 
 import logging
 import os
 import platform
@@ skipping 46 matching lines @@
       print 72 * '-'
       print e.output
       print 72 * '-'
       return 1
     except OSError as e:
       print "  Failed to start test"
       return 1
 
     test_list = gtest_list_tests(list_output)
     for test in test_list:
-      command_line = [mojo_shell, apptest + " --gtest_filter=" + test]
+      # TODO(msw): enable passing arguments to tests down from the test harness.
+      command_line = [
+          mojo_shell,
+          "--args-for={0} --example_apptest_arg --gtest_filter={1}".format(
+              apptest, test),
+          apptest]
 
       _logging.debug("Running %s..." % command_line)
       try:
         # TODO(msw): Need to fail on errors! mojo_shell always exits with 0!
         subprocess.check_output(command_line, stderr=subprocess.STDOUT)
         _logging.debug("Succeeded")
       except subprocess.CalledProcessError as e:
         print "Failed with exit code %d and output:" % e.returncode
         print 72 * '-'
         print e.output
         print 72 * '-'
         return 1
       except OSError as e:
         print "  Failed to start test"
         return 1
     print "Succeeded"
 
   return 0
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))