clean use_emulator option for inconsistence issue

build/android/run_tests.py

 #!/usr/bin/env python
 #
 # Copyright (c) 2012 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.
 
 """Runs all the native unit tests.
 
 1. Copy over test binary to /data/local on device.
 2. Resources: chrome/unit_tests requires resources (chrome.pak and en-US.pak)
@@ skipping 305 matching lines @@
   Args:
     options: options for running the tests.
 
   Returns:
     0 if successful, number of failing tests otherwise.
   """
   attached_devices = []
   buildbot_emulators = []
 
   if options.use_emulator:
-    for n in range(options.use_emulator):
+    for n in range(options.emulator_count):
       t = TimeProfile('Emulator launch %d' % n)
       buildbot_emulator = emulator.Emulator(options.fast_and_loose)
       buildbot_emulator.Launch(kill_all_emulators=n == 0)
       t.Stop()
       buildbot_emulators.append(buildbot_emulator)
       attached_devices.append(buildbot_emulator.device)
     # Wait for all emulators to boot completed.
     map(lambda buildbot_emulator: buildbot_emulator.ConfirmLaunch(True),
         buildbot_emulators)
   elif options.test_device:
@@ skipping 40 matching lines @@
     options.fast_and_loose = True
     options.repeat -= 1
     logging.critical('Repeats left: ' + str(options.repeat))
     return _RunATestSuite(options)
   return len(test_results.failed)
 
 
 def Dispatch(options):
   """Dispatches the tests, sharding if possible.
 
-  If options.use_emulator is True, all tests will be run in a new emulator
+  If options.use_emulator is True, all tests will be run in new emulator
   instance.
 
   Args:
     options: options for running the tests.
 
   Returns:
     0 if successful, number of failing tests otherwise.
   """
   if options.test_suite == 'help':
     ListTestSuites()
@@ skipping 42 matching lines @@
   option_parser.add_option('-a', '--test_arguments', dest='test_arguments',
                            help='Additional arguments to pass to the test')
   option_parser.add_option('-p', dest='performance_test',
                            help='Indicator of performance test',
                            action='store_true')
   option_parser.add_option('-L', dest='log_dump',
                            help='file name of log dump, which will be put in'
                            'subfolder debug_info_dumps under the same directory'
                            'in where the test_suite exists.')
   option_parser.add_option('-e', '--emulator', dest='use_emulator',
-                           help='Run tests in a new instance of emulator',
-                           type='int',
-                           default=0)
+                           action='store_true',
+                           help='Run tests in a new instance of emulator')
+  option_parser.add_option('-n', '--emulator_count',
+                           type='int', default=1,
+                           help='Number of emulators to launch for running the '
+                           'tests.')
   option_parser.add_option('-x', '--xvfb', dest='use_xvfb',
                            action='store_true',
                            help='Use Xvfb around tests (ignored if not Linux)')
   option_parser.add_option('--fast', '--fast_and_loose', dest='fast_and_loose',
                            action='store_true',
                            help='Go faster (but be less stable), '
                            'for quick testing.  Example: when tracking down '
                            'tests that hang to add to the disabled list, '
                            'there is no need to redeploy the test binary '
                            'or data to the device again.  '
@@ skipping 22 matching lines @@
   # the batch (this happens because the exit status is a sum of all failures
   # from all suites, but the buildbot associates the exit status only with the
   # most recent step).
   if options.exit_code:
     return failed_tests_count
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))