Add a new shared page state in pixel_tests.py

content/test/gpu/page_sets/pixel_tests.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.story import story_set as story_set_module
 
 import sys
 
 from gpu_tests import gpu_test_base
 
@@ skipping 47 matching lines @@
 
 
 class DisableMacOverlaysSharedPageState(gpu_test_base.GpuSharedPageState):
   def __init__(self, test, finder_options, story_set):
     super(DisableMacOverlaysSharedPageState, self).__init__(
       test, finder_options, story_set)
     finder_options.browser_options.AppendExtraBrowserArgs(
       ['--disable-mac-overlays'])
 
 
+class EnableExperimentalCanvasFeaturesSharedPageState(
+        gpu_test_base.GpuSharedPageState):
+  def __init__(self, test, finder_options, story_set):
+    super(EnableExperimentalCanvasFeaturesSharedPageState, self).__init__(
+      test, finder_options, story_set)
+    finder_options.browser_options.AppendExtraBrowserArgs(
+      ['--enable-experimental-canvas-features'])
+
 class PixelTestsStorySet(story_set_module.StorySet):
 
   """ Some basic test cases for GPU. """
   def __init__(self, expectations, base_name='Pixel', try_es3=False):
     super(PixelTestsStorySet, self).__init__()
     self._AddAllPages(expectations, base_name, False)
     # Would be better to fetch this from Telemetry.
     # TODO(kbr): enable this on all platforms. Don't know what will
     # happen on Android right now.
     if try_es3 and sys.platform.startswith('darwin'):
@@ skipping 87 matching lines @@
     else:
       es3_suffix = ''
       shared_page_state_class = gpu_test_base.GpuSharedPageState
 
     self.AddStory(PixelTestsPage(
       url='file://../../data/gpu/pixel_offscreenCanvas_webgl_commit_main.html',
       name=base_name + '.OffscreenCanvasWebGLGreenBox' + es3_suffix,
       test_rect=[0, 0, 300, 300],
       revision=1,
       story_set=self,
-      shared_page_state_class=shared_page_state_class,
+      shared_page_state_class=EnableExperimentalCanvasFeaturesSharedPageState,
       expectations=expectations))
 
     self.AddStory(PixelTestsPage(
       url='file://../../data/gpu/pixel_canvas2d.html',
       name=base_name + '.Canvas2DRedBox' + es3_suffix,
       test_rect=[0, 0, 300, 300],
       revision=7,
       story_set=self,
       shared_page_state_class=shared_page_state_class,
       expectations=expectations))
@@ skipping 70 matching lines @@
       story_set=self,
       shared_page_state_class=shared_page_state_class,
       expectations=expectations))
 
   @property
   def allow_mixed_story_states(self):
     # Return True here in order to be able to add the same tests with
     # a different SharedPageState on Mac which tests them with the
     # Core Profile rendering path.
     return True