[Android Buildbot] Revert forking in adb_logcat_monitor.py.

build/android/buildbot/bb_device_steps.py

 #!/usr/bin/env python
 # Copyright (c) 2013 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.
 
 import collections
 import glob
 import hashlib
 import multiprocessing
 import os
@@ skipping 267 matching lines @@
         '--builder-name', builder_name,
         '--gs-bucket', gs_bucket])
 
 
 def EscapeBuilderName(builder_name):
   return re.sub('[ ()]', '_', builder_name)
 
 
 def SpawnLogcatMonitor():
   shutil.rmtree(LOGCAT_DIR, ignore_errors=True)
-  bb_utils.RunCmd([
+  bb_utils.SpawnCmd([
       os.path.join(CHROME_SRC_DIR, 'build', 'android', 'adb_logcat_monitor.py'),
       LOGCAT_DIR])
 
   # Wait for logcat_monitor to pull existing logcat
   RunCmd(['sleep', '5'])
 
 def ProvisionDevices(options):
   bb_annotations.PrintNamedStep('provision_devices')
 
   if not bb_utils.TESTING:
@@ skipping 192 matching lines @@
   setattr(options, 'target', options.factory_properties.get('target', 'Debug'))
   if options.coverage_bucket:
     setattr(options, 'coverage_dir',
             os.path.join(CHROME_OUT_DIR, options.target, 'coverage'))
 
   MainTestWrapper(options)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))