[Telemetry] Remove is_smooth flag.

tools/perf/page_sets/tough_scrolling_cases.py

 # 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 telemetry.page import page as page_module
 from telemetry.page import page_set as page_set_module
 
 
 class ToughScrollingCasesPage(page_module.Page):
 
   def __init__(self, url, page_set):
     super(ToughScrollingCasesPage, self).__init__(url=url, page_set=page_set)
 
   def RunPageInteractions(self, action_runner):
     interaction = action_runner.BeginGestureInteraction(
-        'ScrollAction', is_smooth=True)
+        'ScrollAction')
     action_runner.ScrollPage()
     interaction.End()
 
 class ToughFastScrollingCasesPage(page_module.Page):
 
   def __init__(self, url, name, speed_in_pixels_per_second, page_set):
     super(ToughFastScrollingCasesPage, self).__init__(
       url=url,
       page_set=page_set,
       name=name,
       labels=['fastscrolling'])
     self.speed_in_pixels_per_second = speed_in_pixels_per_second
 
   def RunPageInteractions(self, action_runner):
     interaction = action_runner.BeginGestureInteraction(
-        'ScrollAction', is_smooth=True)
+        'ScrollAction')
     action_runner.ScrollPage(
       direction='down',
       speed_in_pixels_per_second=self.speed_in_pixels_per_second)
     interaction.End()
 
 class ToughScrollingCasesPageSet(page_set_module.PageSet):
 
   """
   Description: A collection of difficult scrolling tests
   """
@@ skipping 25 matching lines @@
       5000, 10000, 15000, 20000, 30000, 40000, 50000, 60000, 75000, 90000
     ]
 
     for name in fast_scrolling_page_name_list:
       for speed in fast_scrolling_speed_list:
         self.AddUserStory(ToughFastScrollingCasesPage(
           'file://tough_scrolling_cases/' + name + '.html',
           name + '_' + str(speed).zfill(5) + '_pixels_per_second',
           speed,
           self))