Move clear_system_cache_for_browser_and_profile_on_start to BrowserOptions

tools/perf/measurements/startup.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.
 
 import json
 
 from telemetry.page import page_measurement
 
 class Startup(page_measurement.PageMeasurement):
   """Performs a measurement of Chromium's startup performance.
@@ skipping 18 matching lines @@
                       help='Clear the OS disk cache before performing the test')
     parser.add_option('--warm', action='store_true',
                       help='Start up with everything already cached')
 
   def CustomizeBrowserOptions(self, options):
     # TODO: Once the bots start running benchmarks, enforce that either --warm
     # or --cold is explicitly specified.
     # assert options.warm != options.cold, \
     #     "You must specify either --warm or --cold"
     if options.cold:
-      options.clear_sytem_cache_for_browser_and_profile_on_start = True
+      browser_options = options.browser_options
+      browser_options.clear_sytem_cache_for_browser_and_profile_on_start = True
     else:
       self.discard_first_result = True
 
     options.AppendExtraBrowserArgs([
         '--enable-stats-collection-bindings',
 
         # Old commandline flags used for reference builds.
         '--dom-automation',
         '--reduce-security-for-dom-automation-tests'
     ])
@@ skipping 13 matching lines @@
 
       if 'sum' in result:
         # For all the histograms logged here, there's a single entry so sum
         # is the exact value for that entry.
         measured_time = result['sum']
       elif 'buckets' in result:
         measured_time = \
             (result['buckets'][0]['high'] + result['buckets'][0]['low']) / 2
 
       results.Add(display_name, 'ms', measured_time)