[BattOr] Add ability to platform object to detect BattOrs.

telemetry/telemetry/internal/platform/platform_backend.py

 # Copyright 2013 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.
 
 import weakref
 
+from battor import battor_wrapper
 from telemetry.internal import forwarders
 from telemetry.internal.forwarders import do_nothing_forwarder
 from telemetry.internal.platform import network_controller_backend
 from telemetry.internal.platform import tracing_controller_backend
 
 
 # pylint: disable=unused-argument
 
 class PlatformBackend(object):
 
@@ skipping 269 matching lines @@
   def PathExists(self, path, timeout=None, retries=None):
     """Tests whether the given path exists on the target platform.
     Args:
       path: path in request.
       timeout: timeout.
       retries: num of retries.
     Return:
       Whether the path exists on the target platform.
     """
     raise NotImplementedError()
+
+  def HasBattOrConnected(self):
+    return battor_wrapper.IsBattOrConnected(self.GetOSName())