Modify list_system_health_stories to generate_system_health_csv

tools/perf/page_sets/system_health/long_running_stories.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.
 
 from page_sets.login_helpers import google_login
 from page_sets.system_health import platforms
 from page_sets.system_health import system_health_story
 
 from telemetry import decorators
 
@@ skipping 12 matching lines @@
     super(_LongRunningStory, self).RunPageInteractions(action_runner)
     if self.BACKGROUND:
       action_runner.tab.browser.tabs.New()
     if self._take_memory_measurement:
       action_runner.MeasureMemory()
     for _ in xrange(STEPS):
       action_runner.Wait(SAMPLING_INTERVAL_IN_SECONDS)
       if self._take_memory_measurement:
         action_runner.MeasureMemory()
 
+  @classmethod
+  def GenerateStoryDescription(cls):
+    if cls.BACKGROUND:
+      return ('Load %s then open a new blank tab and let the loaded page stay '
+              'in background for %s seconds.' % (cls.URL, IDLE_TIME_IN_SECONDS))
+    else:
+      return ('Load %s then let it stay in foreground for %s seconds.' %
+              (cls.URL, IDLE_TIME_IN_SECONDS))
+
 
 ##############################################################################
 # Long running Gmail stories.
 ##############################################################################
 
 # TODO(rnephew): Merge _Login() and _DidLoadDocument() with methods in
 # loading_stories.
 class _LongRunningGmailBase(_LongRunningStory):
   URL = 'https://mail.google.com/mail/'
   ABSTRACT_STORY = True
@@ skipping 53 matching lines @@
 @decorators.Disabled('android-webview',  # Weview does not have tabs.
                      'android')  # crbug.com/657433
 class LongRunningGmailMobileBackgroundStory(_LongRunningGmailMobileBase):
   BACKGROUND = True
   NAME = 'long_running:tools:gmail-background'
 
 
 class LongRunningGmailDesktopBackgroundStory(_LongRunningGmailDesktopBase):
   BACKGROUND = True
   NAME = 'long_running:tools:gmail-background'