[tools/perf] Remove smoothness.tough_scrolling_while_zoomed_in_cases benchmark

tools/perf/page_sets/tough_scrolling_while_zoomed_in_cases.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.
-from page_sets import diagonal_scrolling_supported_shared_state
-
-from telemetry.page import page as page_module
-from telemetry import story
-
-
-class ToughScrollingWhileZoomedInCasesPage(page_module.Page):
-
-  def __init__(self, url, page_set):
-    super(ToughScrollingWhileZoomedInCasesPage, self).__init__(
-        url=url,
-        page_set=page_set,
-        shared_page_state_class=(
-            diagonal_scrolling_supported_shared_state.
-            DiagonalScrollingSupportedSharedState))
-
-  def RunPageInteractions(self, action_runner):
-    # First, zoom into the page
-    action_runner.PinchPage(
-        scale_factor=20.0,
-        speed_in_pixels_per_second=10000)
-    # 20.0 was chosen because at the time it was close to the maximum.
-    # The more zoomed in, the more noticeable the tile rasterization.
-    #
-    # 10,000 was chosen to complete this pre-step quickly.
-
-    # Then start measurements
-    with action_runner.CreateGestureInteraction('ScrollAction'):
-      # And begin the diagonal scroll
-      action_runner.ScrollPage(
-          direction='downright',
-          # 10,000 was chosen because it is fast enough to completely stress the
-          # rasterization (on a Nexus 5) without saturating results.
-          speed_in_pixels_per_second=10000)
-
-
-class ToughScrollingWhileZoomedInCasesPageSet(story.StorySet):
-  """
-  Description: A collection of difficult scrolling tests
-  """
-
-  def __init__(self):
-    super(ToughScrollingWhileZoomedInCasesPageSet, self).__init__(
-        archive_data_file='data/tough_pinch_zoom_cases.json',
-        cloud_storage_bucket=story.PARTNER_BUCKET)
-
-    # The following URLs were chosen because they tend to have >15%
-    # mean_pixels_approximated at this scrolling speed.
-    urls_list = [
-        'file://tough_scrolling_cases/background_fixed.html',
-        'file://tough_scrolling_cases/fixed_nonstacking.html',
-        'file://tough_scrolling_cases/iframe_scrolls.html',
-        'file://tough_scrolling_cases/wheel_div_prevdefault.html'
-    ]
-
-    for url in urls_list:
-      self.AddStory(ToughScrollingWhileZoomedInCasesPage(url, self))