[Android] Dedup content_browsertests test setup from gtests.

build/android/pylib/android_commands.py

 # Copyright (c) 2012 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.
 
 """Provides an interface to communicate with the device via the adb command.
 
 Assumes adb binary is currently on system path.
 """
 
 import collections
@@ skipping 244 matching lines @@
     if self._device:
       device_repr = self._device[-4:]
     else:
       device_repr = '????'
     logging.info('[%s]> %s', device_repr, cmd)
 
   def Adb(self):
     """Returns our AdbInterface to avoid us wrapping all its methods."""
     return self._adb
 
+  def GetDevice(self):
+    """Returns the device serial."""
+    return self._device
+
   def IsOnline(self):
     """Checks whether the device is online.
 
     Returns:
       True if device is in 'device' mode, False otherwise.
     """
     out = self._adb.SendCommand('get-state')
     return out.strip() == 'device'
 
   def IsRootEnabled(self):
@@ skipping 1193 matching lines @@
   """
   def __init__(self, output):
     self._output = output
 
   def write(self, data):
     data = data.replace('\r\r\n', '\n')
     self._output.write(data)
 
   def flush(self):
     self._output.flush()