[Android] Add functionality to flash devices.

build/android/devil/android/device_errors.py

Index: build/android/devil/android/device_errors.py
diff --git a/build/android/devil/android/device_errors.py b/build/android/devil/android/device_errors.py
index fde7d1aa99f3b49923be5ebf348567b0959905fd..58990f56b9e26ee99a1f3f7389b10d0a098cf4a6 100644
--- a/build/android/devil/android/device_errors.py
+++ b/build/android/devil/android/device_errors.py
@@ -42,6 +42,16 @@ class AdbCommandFailedError(CommandFailedError):
     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."""