[system-health] Re-enable stories failing smoke test due to CSSImageValue issue

tools/perf/benchmarks/system_health_smoke_test.py

 # Copyright 2016 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.
 
 """Run all system health stories used by system health benchmarks.
 
 Only memory benchmarks are used when running these stories to make the total
 cycle time manageable. Other system health benchmarks should be using the same
 stories as memory ones, only with fewer actions (no memory dumping).
 """
@@ skipping 14 matching lines @@
 
 def GetSystemHealthBenchmarksToSmokeTest():
   sh_benchmark_classes = discover.DiscoverClassesInModule(
       system_health, perf_benchmark.PerfBenchmark,
       index_by_class_name=True).values()
   return list(b for b in sh_benchmark_classes if
               b.Name().startswith('system_health.memory'))
 
 
 _DISABLED_TESTS = frozenset({
-  # crbug.com/630215
-  'benchmarks.system_health_smoke_test.SystemHealthBenchmarkSmokeTest.system_health.memory_desktop.browse:news:nytimes',  # pylint: disable=line-too-long
-  'benchmarks.system_health_smoke_test.SystemHealthBenchmarkSmokeTest.system_health.memory_desktop.browse:news:reddit',  # pylint: disable=line-too-long
   # crbug.com/622409
   'benchmarks.system_health_smoke_test.SystemHealthBenchmarkSmokeTest.system_health.memory_desktop.browse:news:cnn',  # pylint: disable=line-too-long
   # crbug.com/629123
   'benchmarks.system_health_smoke_test.SystemHealthBenchmarkSmokeTest.system_health.memory_mobile.browse:news:hackernews',  # pylint: disable=line-too-long
   'benchmarks.system_health_smoke_test.SystemHealthBenchmarkSmokeTest.system_health.memory_mobile.browse:news:nytimes',  # pylint: disable=line-too-long
 })
 
 
 def _GenerateSmokeTestCase(benchmark_class, story_to_smoke_test):
 
@@ skipping 78 matching lines @@
     # parsed during test time which happens after load_tests are called.
     # Since none of our system health benchmarks creates stories based on
     # command line options, it should be ok to pass options=None to
     # CreateStorySet.
     for story_to_smoke_test in (
         benchmark_class().CreateStorySet(options=None).stories):
       suite.addTest(
           _GenerateSmokeTestCase(benchmark_class, story_to_smoke_test))
 
   return suite