[Android] Add functionality to flash devices.

build/android/devil/android/device_errors.py

 # Copyright 2014 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.
 
 """
 Exception classes raised by AdbWrapper and DeviceUtils.
 """
 
 from devil import base_error
 from devil.utils import cmd_helper
@@ skipping 24 matching lines @@
         message.append('with exit status %s ' % self.status)
       if output:
         message.append('and output:\n')
         message.extend('- %s\n' % line for line in output.splitlines())
       else:
         message.append('and no output.')
       message = ''.join(message)
     super(AdbCommandFailedError, self).__init__(message, device_serial)
 
 
+class FastbootCommandFailedError(AdbCommandFailedError):

[perezju, 2015/10/29 10:09:52]

Ohh, but not like that. Otherwise trying to catch AdbCommandFailedError will
also catch FastbootCommandFailedError. Instead maybe, at least to start, create
a _BaseCommandFailedError with most of the implementation, and then create two
subclasses, one for AdbCommandFailedError and one for
FastbootCommandFailedError.

[rnephew (Reviews Here), 2015/10/29 16:37:34]

Done.

+  """Exception for fastboot command failures."""
+
+  def __init__(self, args, output, status=None, device_serial=None,
+               message=None):
+    super(FastbootCommandFailedError, self).__init__(
+        args, output, status=status, message=message,
+        device_serial=device_serial)
+
+
 class DeviceVersionError(CommandFailedError):
   """Exception for device version failures."""
 
   def __init__(self, message, device_serial=None):
     super(DeviceVersionError, self).__init__(message, device_serial)
 
 
 class AdbShellCommandFailedError(AdbCommandFailedError):
   """Exception for shell command failures run via adb."""
 
@@ skipping 25 matching lines @@
   """Exception for device unreachable failures."""
   pass
 
 
 class NoDevicesError(base_error.BaseError):
   """Exception for having no devices attached."""
 
   def __init__(self):
     super(NoDevicesError, self).__init__(
         'No devices attached.', is_infra_error=True)