Add exit code for infra failures to testrunner script.

build/android/pylib/device/device_errors.py

Index: build/android/pylib/device/device_errors.py
diff --git a/build/android/pylib/device/device_errors.py b/build/android/pylib/device/device_errors.py
index c47c9668ed1a37b19556d6b5bf3e4262adac39f8..01040cb09464313d72d63ca78d73d55ce8d6b96f 100644
--- a/build/android/pylib/device/device_errors.py
+++ b/build/android/pylib/device/device_errors.py
@@ -7,14 +7,10 @@ Exception classes raised by AdbWrapper and DeviceUtils.
 """
 
 from pylib import cmd_helper
+from pylib.base import base_error
 
 
-class BaseError(Exception):
-  """Base exception for all device and command errors."""
-  pass
-
-
-class CommandFailedError(BaseError):
+class CommandFailedError(base_error.BaseError):
   """Exception for command failures."""
 
   def __init__(self, message, device_serial=None):
@@ -64,19 +60,18 @@ class AdbShellCommandFailedError(AdbCommandFailedError):
       ['shell', command], output, status, device_serial, message)
 
 
-class CommandTimeoutError(BaseError):
+class CommandTimeoutError(base_error.BaseError):
   """Exception for command timeouts."""
   pass
 
 
-class DeviceUnreachableError(BaseError):
+class DeviceUnreachableError(base_error.BaseError):
   """Exception for device unreachable failures."""
   pass
 
 
-class NoDevicesError(BaseError):
+class NoDevicesError(base_error.BaseError):
   """Exception for having no devices attached."""
 
   def __init__(self):
     super(NoDevicesError, self).__init__('No devices attached.')
-