[Telemetry] Make "discard_first_result" apply to user_stories too.

tools/perf/benchmarks/page_cycler.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.
 
 from measurements import page_cycler
 import page_sets
 from telemetry import benchmark
 
 
 class _PageCycler(benchmark.Benchmark):
   options = {'pageset_repeat': 6}
+  cold_load_percent = 50  # % of page visits for which a cold load is forced
 
   @classmethod
   def Name(cls):
     return 'page_cycler'
 
   @classmethod
   def AddBenchmarkCommandLineArgs(cls, parser):
     parser.add_option('--report-speed-index',
         action='store_true',
         help='Enable the speed index metric.')
 
-    parser.add_option('--cold-load-percent', type='int', default=50,
-                      help='%d of page visits for which a cold load is forced')
+  @classmethod
+  def ValueCanBeAddedPredicate(cls, _, is_first_result):
+    return cls.cold_load_percent > 0 or not is_first_result
 
   def CreatePageTest(self, options):
     return page_cycler.PageCycler(
         page_repeat = options.page_repeat,
         pageset_repeat = options.pageset_repeat,
-        cold_load_percent = options.cold_load_percent,
+        cold_load_percent = self.cold_load_percent,
         report_speed_index = options.report_speed_index)
 
 
 # This is an old page set, we intend to remove it after more modern benchmarks
 # work on CrOS.
 @benchmark.Enabled('chromeos')
 class PageCyclerDhtml(_PageCycler):
   """Benchmarks for various DHTML operations like simple animations."""
   page_set = page_sets.DhtmlPageSet
 
@@ skipping 91 matching lines @@
   """Measures load time of the top 10 sites under simulated cable network.
 
   Recorded in June, 2013.  Pages are loaded under the simplisticly simulated
   bandwidth and RTT constraints of a cable modem (5Mbit/s down, 1Mbit/s up,
   28ms RTT). Contention is realistically simulated, but slow start is not.
   DNS lookups are 'free'.
   """
   tag = 'netsim'
   page_set = page_sets.Top10PageSet
   options = {
-      'cold_load_percent': 100,
       'extra_wpr_args_as_string': '--shaping_type=proxy --net=cable',
       'pageset_repeat': 6,
   }
+  cold_load_percent = 100
 
   @classmethod
   def Name(cls):
     return 'page_cycler.netsim.top_10'
 
   def CreatePageTest(self, options):
     return page_cycler.PageCycler(
         page_repeat = options.page_repeat,
         pageset_repeat = options.pageset_repeat,
-        cold_load_percent = options.cold_load_percent,
+        cold_load_percent = self.cold_load_percent,
         report_speed_index = options.report_speed_index,
         clear_cache_before_each_run = True)
 
 
 @benchmark.Enabled('android')
 class PageCyclerTop10Mobile(_PageCycler):
   """Page load time benchmark for the top 10 mobile web pages.
 
   Runs against pages recorded in November, 2013.
   """
@@ skipping 60 matching lines @@
 
   def CreatePageSet(self, options):
     return page_sets.Typical25PageSet(run_no_page_interactions=True)
 
 @benchmark.Disabled # crbug.com/443730
 class PageCyclerBigJs(_PageCycler):
   page_set = page_sets.BigJsPageSet
   @classmethod
   def Name(cls):
     return 'page_cycler.big_js'