webrtc: Fix missing port forwarding on CrOS

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
@@ skipping 91 matching lines @@
     assert browser not in self._running_browser_backends
     self._running_browser_backends.add(browser_backend)
 
   def WillCloseBrowser(self, browser, browser_backend):
     is_last_browser = len(self._running_browser_backends) <= 1
     if is_last_browser:
       self.SetFullPerformanceModeEnabled(False)
 
     self._running_browser_backends.discard(browser_backend)
 
+  def CreatePortForwarder(self, port_pair, use_remote_port_forwarding):
+    """Use forwarder_factory to create a port forwarder."""
+    raise NotImplementedError()
+
+  def IsRemoteDevice(self):
+    """Check if target platform is on remote device.
+
+    Returns True if device is remote, i.e. android
+    device connected via adb or running a test with
+    remote option specifying the ip address of a cros device.
+    Return False for other platforms.
+    """
+    return False
+
   def IsDisplayTracingSupported(self):
     return False
 
   def StartDisplayTracing(self):
     """Start gathering a trace with frame timestamps close to physical
     display."""
     raise NotImplementedError()
 
   def StopDisplayTracing(self):
     """Stop gathering a trace with frame timestamps close to physical display.
@@ skipping 176 matching lines @@
     Return:
       Whether the path exists on the target platform.
     """
     raise NotImplementedError()
 
   def HasBattOrConnected(self):
     return battor_wrapper.IsBattOrConnected(self.GetOSName())
 
   def WaitForBatteryTemperature(self, temp):
     pass