[Android] Thread names reflect the device serial number they are associated with.

build/android/pylib/utils/run_tests_helper.py

 # 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.
 
 """Helper functions common to native, java and python test runners."""
 
 import logging
 import os
 import time
 
 
 class CustomFormatter(logging.Formatter):
   """Custom log formatter."""
 
   #override
-  def __init__(self, fmt=''):
+  def __init__(self, fmt='%(threadName)-4s  %(message)s'):
     # Can't use super() because in older Python versions logging.Formatter does
     # not inherit from object.
     logging.Formatter.__init__(self, fmt=fmt)
     self._creation_time = time.time()
 
   #override
   def format(self, record):
     # Can't use super() because in older Python versions logging.Formatter does
     # not inherit from object.
     msg = logging.Formatter.format(self, record)
+    if 'MainThread' in msg[:19]:
+      msg = msg.replace('MainThread', 'Main', 1)
     timediff = str(int(time.time() - self._creation_time))
-    return '%s %ss  %s' % (record.levelname[0], timediff.rjust(4), msg)
+    return '%s %ss %s' % (record.levelname[0], timediff.rjust(4), msg)
 
 
 def GetExpectations(file_name):
   """Returns a list of test names in the |file_name| test expectations file."""
   if not file_name or not os.path.exists(file_name):
     return []
   return [x for x in [x.strip() for x in file(file_name).readlines()]
           if x and x[0] != '#']
 
 
 def SetLogLevel(verbose_count):
   """Sets log level as |verbose_count|."""
   log_level = logging.WARNING  # Default.
   if verbose_count == 1:
     log_level = logging.INFO
   elif verbose_count >= 2:
     log_level = logging.DEBUG
   logger = logging.getLogger()
   logger.setLevel(log_level)
   custom_handler = logging.StreamHandler()
   custom_handler.setFormatter(CustomFormatter())
   logging.getLogger().addHandler(custom_handler)