[Telemetry] Make session restore benchmark not require arguments.

tools/perf/measurements/session_restore.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 collections
+import logging
+import sys
 
 from measurements import startup
 from metrics import cpu
 from metrics import startup_metric
 from telemetry.core import util
 
+
 class SessionRestore(startup.Startup):
   """Performs a measurement of Chromium's Session restore performance.
 
   This test is meant to be run against a generated profile.
   This test inherits support for the --warm or --cold command line options -
   see startup.py for details.
   """
 
   def __init__(self, action_name_to_run = ''):
     super(SessionRestore, self).__init__(action_name_to_run=action_name_to_run)
     self.close_tabs_before_run = False
     self._cpu_metric = None
 
   def CustomizeBrowserOptions(self, options):
     super(SessionRestore, self).CustomizeBrowserOptions(options)
     options.AppendExtraBrowserArgs([
         '--restore-last-session'
     ])
+    if not options.profile_dir:

[dtu, 2014/06/05 01:35:28]

Goes into ProcessCommandLineArgs still

+      logging.critical(
+          '--profile-dir or --profile-type is required for a session restore.\n'
+          'For more information see: http://goo.gl/ngdGD5')
+      sys.exit(1)
 
   def TabForPage(self, page, browser):
     # Detect that the session restore has completed.
     util.WaitFor(lambda: len(browser.tabs), 30)
     return browser.tabs[0]
 
   def CanRunForPage(self, page):
     # No matter how many pages in the pageset, just perform one test iteration.
     return page.page_set.pages.index(page) == 0
 
@@ skipping 22 matching lines @@
   def MeasurePage(self, page, tab, results):
     tab.browser.foreground_tab.WaitForDocumentReadyStateToBeComplete()
 
     # Record CPU usage from browser start to when the foreground page is loaded.
     self._cpu_metric.Stop(None, None)
     self._cpu_metric.AddResults(tab, results, 'cpu_utilization')
 
     startup_metric.StartupMetric().AddResults(tab, results)
 
     # TODO(jeremy): Measure time to load - first, last and frontmost tab here.