Don't stop because we couldn't restart usb devices.

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 274 matching lines @@
   options, args = parser.parse_args()
   if args:
     parser.error('Unknown options %s' % args)
 
   if options.restart_usb:
     expected_devices = GetLastDevices(os.path.abspath(options.out_dir))
     devices = android_commands.GetAttachedDevices()
     # Only restart usb if devices are missing
     if set(expected_devices) != set(devices):
       KillAllAdb()
+      retries = 5
       if RestartUsb():
-        return 1
-      retries = 5
+        bb_annotations.PrintWarning()
+        print "USB reset stage failed, continuing anyway."

[bulach, 2013/11/05 18:21:09]

nit: I think the PrintWarning() needs to come after the message, and it should
be single quotes for print..

there was some debate about this return code when it was added, not quite sure
what was the motiviation, but I think your patch is a good thing, there's no
reason not to keep trying, this restart_usb unfortunately is not as
deterministic as it should've been..

+        retries = 0
       while retries:
         time.sleep(1)
         devices = android_commands.GetAttachedDevices()
         if set(expected_devices) == set(devices):
           break
         retries -= 1
 
   devices = android_commands.GetAttachedDevices()
   # TODO(navabi): Test to make sure this fails and then fix call
   offline_devices = android_commands.GetAttachedDevices(hardware=False,
@@ skipping 42 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())