webrtc: Fix missing port forwarding on CrOS

telemetry/telemetry/internal/platform/cros_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 logging
 
 from telemetry import decorators
 from telemetry.core import cros_interface
 from telemetry.core import platform
 from telemetry.core import util
@@ skipping 37 matching lines @@
   def forwarder_factory(self):
     if not self._forwarder_factory:
       self._forwarder_factory = cros_forwarder.CrOsForwarderFactory(self._cri)
     return self._forwarder_factory
 
   def GetRemotePort(self, port):
     if self._cri.local:
       return port
     return self._cri.GetRemotePort()
 
+  def CreatePortForwarder(self, port_pair, use_remote_port_forwarding=False):
+    return self.forwarder_factory.Create(port_pair, use_remote_port_forwarding)
+
+  def IsDeviceRemote(self):
+    # Check if CrOS device is remote.
+    return self._cri and not self._cri.local
+
   def IsThermallyThrottled(self):
     raise NotImplementedError()
 
   def HasBeenThermallyThrottled(self):
     raise NotImplementedError()
 
   def RunCommand(self, args):
     if not isinstance(args, list):
       args = [args]
     stdout, stderr = self._cri.RunCmdOnDevice(args)
@@ skipping 93 matching lines @@
       logging.warning(
           'PathExists: params timeout and retries are not support on CrOS.')
     return self._cri.FileExistsOnDevice(path)
 
   def CanTakeScreenshot(self):
     # crbug.com/609001: screenshots don't work on VMs.
     return not self.cri.IsRunningOnVM()
 
   def TakeScreenshot(self, file_path):
     return self._cri.TakeScreenshot(file_path)