[system-health] Generalize loading stories to single-page stories

tools/perf/benchmarks/system_health.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.
 
 import re
 
 from core import perf_benchmark
 from telemetry import benchmark
 from telemetry.timeline import tracing_category_filter
 from telemetry.web_perf import timeline_based_measurement
@@ skipping 73 matching lines @@
 
   @classmethod
   def ValueCanBeAddedPredicate(cls, value, is_first_result):
     # TODO(crbug.com/610962): Remove this stopgap when the perf dashboard
     # is able to cope with the data load generated by TBMv2 metrics.
     return not _IGNORED_STATS_RE.search(value.name)
 
 
 class DesktopMemorySystemHealth(_MemorySystemHealthBenchmark):
   """Desktop Chrome Memory System Health Benchmark."""
-  page_set = page_sets.DesktopMemorySystemHealthStorySet
+  page_set = page_sets.DesktopSystemHealthStorySet
 
   @classmethod
   def ShouldDisable(cls, possible_browser):
     return possible_browser.platform.GetDeviceTypeName() != 'Desktop'
 
 
 class MobileMemorySystemHealth(_MemorySystemHealthBenchmark):
   """Mobile Chrome Memory System Health Benchmark."""
-  page_set = page_sets.MobileMemorySystemHealthStorySet
+  page_set = page_sets.MobileSystemHealthStorySet
 
   @classmethod
   def ShouldDisable(cls, possible_browser):
     # http://crbug.com/612144 (reference on Nexus 5X).
     return possible_browser.platform.GetDeviceTypeName() == 'Desktop' or (
         possible_browser.browser_type == 'reference' and
         possible_browser.platform.GetDeviceTypeName() == 'Nexus 5X')
 
 @benchmark.Enabled('android-webview')
 class WebviewStartupSystemHealthBenchmark(perf_benchmark.PerfBenchmark):
@@ skipping 14 matching lines @@
     options.config.atrace_config.app_name = 'org.chromium.webview_shell'
     return options
 
   @classmethod
   def ShouldTearDownStateAfterEachStoryRun(cls):
     return True
 
   @classmethod
   def Name(cls):
     return 'system_health.webview_startup'