Android: fixes bb_device_status_check.

build/android/buildbot/bb_device_status_check.py

 #!/usr/bin/env python
 #
 # Copyright 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.
 
 """A class to keep track of devices across builds and report state."""
 import logging
 import optparse
 import os
@@ skipping 41 matching lines @@
     install_speed = 'Unknown'
   if 'Error' in battery:
     ac_power = 'Unknown'
     battery_level = 'Unknown'
     battery_temp = 'Unknown'
   else:
     ac_power = re.findall('AC powered: (\w+)', battery)[0]
     battery_level = int(re.findall('level: (\d+)', battery)[0])
     battery_temp = float(re.findall('temperature: (\d+)', battery)[0]) / 10
   sub_info = device_adb.GetSubscriberInfo()
-  imei_slice = re.findall('Device ID = (\d+)', sub_info)[0][-6:]
+  imei_slice = ''
+  if sub_info and len(sub_info):
+    imei_slice = re.findall('Device ID = (\d+)', sub_info)[0][-6:]
   report = ['Device %s (%s)' % (serial, device_type),
             '  Build: %s (%s)' %
               (device_build, device_adb.GetBuildFingerprint()),
             '  Battery: %s%%' % battery_level,
             '  Battery temp: %s' % battery_temp,
             '  IMEI slice: %s' % imei_slice,
             '  Wifi IP: %s' % device_adb.GetWifiIP(),
             '  Install Speed: %s KB/s' % install_speed,
             '']
 
@@ skipping 165 matching lines @@
     # devices with critically low battery or install speed. Remove those devices
     # from testing, allowing build to continue with good devices.
     return 1
 
   if not devices:
     return 1
 
 
 if __name__ == '__main__':
   sys.exit(main())