[Telemetry] Add API for updating ts_proxy_server's traffic settings

telemetry/telemetry/testing/fakes/__init__.py

 # Copyright 2015 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 fakes for several of Telemetry's internal objects.
 
 These allow code like story_runner and Benchmark to be run and tested
 without compiling or starting a browser. Class names prepended with an
 underscore are intended to be implementation details, and should not
 be subclassed; however, some, like _FakeBrowser, have public APIs that
@@ skipping 279 matching lines @@
   def __init__(self):
     self.wpr_mode = None
     self.extra_wpr_args = None
     self.is_replay_active = False
     self.is_open = False
     self.use_live_traffic = None
 
   def InitializeIfNeeded(self, use_live_traffic=False):
     self.use_live_traffic = use_live_traffic
 
+  def UpdateTrafficSettings(self, round_trip_latency_ms=None,
+      download_bandwidth_kbps=None, upload_bandwidth_kbps=None):
+    pass
+
   def Open(self, wpr_mode, extra_wpr_args):
     self.wpr_mode = wpr_mode
     self.extra_wpr_args = extra_wpr_args
     self.is_open = True
 
   def Close(self):
     self.wpr_mode = None
     self.extra_wpr_args = None
     self.is_replay_active = False
     self.is_open = False
@@ skipping 159 matching lines @@
 
     self._notifications.pop(0)
     self._mock_timer.SetTime(time + 1)
     if kind == self._NOTIFICATION_EVENT:
       self._handler(response)
     elif kind == self._NOTIFICATION_CALLBACK:
       callback = self._pending_callbacks.get(response['method']).pop(0)
       callback(response)
     else:
       raise Exception('Unexpected response type')