Disable failing smoothness.tough_canvas_cases benchmark on linux.

tools/perf/benchmarks/smoothness.py

 # Copyright 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 multiprocessing
 
 from core import perf_benchmark
 
 from benchmarks import silk_flags
 from measurements import smoothness
 import page_sets
@@ skipping 81 matching lines @@
 
   Measures frame rate and a variety of other statistics.  """
   page_set = page_sets.ToughPathRenderingCasesPageSet
 
   @classmethod
   def Name(cls):
     return 'smoothness.tough_path_rendering_cases'
 
 
 @benchmark.Disabled('android')  # crbug.com/526901
+@benchmark.Disabled('linux')  # crbug.com/715607
 @benchmark.Owner(emails=['junov@chromium.org'])
 class SmoothnessToughCanvasCases(_Smoothness):
   """Measures frame rate and a variety of other statistics.
 
   Uses a selection of pages making use of the 2D Canvas API.
   """
   page_set = page_sets.ToughCanvasCasesPageSet
 
   def SetExtraBrowserOptions(self, options):
     options.AppendExtraBrowserArgs('--enable-experimental-canvas-features')
@@ skipping 423 matching lines @@
   """Measures rendering statistics while scrolling advertisements."""
   page_set = page_sets.SyntheticToughWebglAdCasesPageSet
 
   @classmethod
   def Name(cls):
     return 'smoothness.tough_webgl_ad_cases'
 
   @classmethod
   def ShouldDisable(cls, possible_browser):
     return cls.IsSvelte(possible_browser)  # http://crbug.com/574485