telemetry: Add tough scheduling cases

tools/perf/benchmarks/smoothness.py

 # Copyright (c) 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 sys
 
 from telemetry import test
 
 from measurements import smoothness
 
@@ skipping 11 matching lines @@
   enabled = sys.platform != 'darwin'
   page_set = 'page_sets/tough_canvas_cases.json'
 
 
 class SmoothnessKeyMobileSites(test.Test):
   """Measures rendering statistics while scrolling down the key mobile sites.
 
   http://www.chromium.org/developers/design-documents/rendering-benchmarks"""
   test = smoothness.Smoothness
   page_set = 'page_sets/key_mobile_sites.json'
+
+
+class SmoothnessToughSchedulingCases(test.Test):
+  """Measures rendering statistics while interacting with pages that have
+  challenging scheduling properties.
+
+  https://docs.google.com/a/chromium.org/document/d/
+      17yhE5Po9By0sCdM1yZT3LiUECaUr_94rQt9j-4tOQIM/view"""
+  test = smoothness.Smoothness
+  page_set = 'page_sets/tough_scheduling_cases.json'