Add option to wipe device.

build/android/pylib/device/device_utils.py

Index: build/android/pylib/device/device_utils.py
diff --git a/build/android/pylib/device/device_utils.py b/build/android/pylib/device/device_utils.py
index c8a5c3a48124107fe9142489c6cf999e4d143eb4..93e364eb426599cdcd32abc69fc1ce9122f3f96d 100644
--- a/build/android/pylib/device/device_utils.py
+++ b/build/android/pylib/device/device_utils.py
@@ -8,14 +8,49 @@ Provides a variety of device interactions based on adb.
 Eventually, this will be based on adb_wrapper.
 """
 
+import multiprocessing
+import os
+import sys
 import pylib.android_commands
 from pylib.device import adb_wrapper
 
+CHROME_SRC_DIR = os.path.abspath(
+    os.path.join(os.path.dirname(__file__), '..', '..', '..', '..'))
+sys.path.append(os.path.join(
+    CHROME_SRC_DIR, 'third_party', 'android_testrunner'))
+import errors
 
 def GetAVDs():
   return pylib.android_commands.GetAVDs()
 
 
+# multiprocessing map_async requires a top-level function for pickle library.
+def RebootDeviceSafe(device):
+  """Reboot a device, wait for it to start, and squelch timeout exceptions."""
+  try:
+    DeviceUtils(device).old_interface.Reboot(True)
+  except errors.DeviceUnresponsiveError as e:
+    return e
+
+
+def RebootDevices():
+  """Reboot all attached and online devices."""
+  devices = pylib.android_commands.GetAttachedDevices()
+  print 'Rebooting: %s' % devices
+  if devices:
+    pool = multiprocessing.Pool(len(devices))
+    results = pool.map_async(RebootDeviceSafe, devices).get(99999)
+
+    for device, result in zip(devices, results):
+      if result:
+        print '%s failed to startup.' % device
+
+    if any(results):
+      print 'RebootDevices() Warning: %s' % results
+    else:
+      print 'Reboots complete.'
+
+
 class DeviceUtils(object):
 
   def __init__(self, device):