old_contents: # Copyright 2014 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.
  
  from core import perf_benchmark
  
  from measurements import webrtc
  from telemetry import benchmark
  import page_sets
  
  
  @benchmark.Disabled('reference')
  class WebRTC(perf_benchmark.PerfBenchmark):
    """Obtains WebRTC metrics for a real-time video tests."""
    test = webrtc.WebRTC
    page_set = page_sets.WebrtcCasesPageSet
    @classmethod
    def Name(cls):
      return 'webrtc.webrtc_cases'
  
  
new_contents: # Copyright 2014 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.
  
  from core import perf_benchmark
  
  from measurements import webrtc
  from telemetry import benchmark
  import page_sets
  
  
  # Disabled because the reference set becomes flaky with the new
  # https:// page set introduced in http://crbug.com/523517.
  # Try removing once the Chrome used for ref builds advances
  # past blink commit pos 200986.
  @benchmark.Disabled('reference')
  class WebRTC(perf_benchmark.PerfBenchmark):
    """Obtains WebRTC metrics for a real-time video tests."""
    test = webrtc.WebRTC
    page_set = page_sets.WebrtcCasesPageSet
    @classmethod
    def Name(cls):
      return 'webrtc.webrtc_cases'
  
  
subject: Add a comment saying why the WebRTC ref page set was disabled.