[tools/perf] Initialize network_controller_backend in dual_browser_story_shared_state

tools/perf/page_sets/dual_browser_story.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 collections
 import logging
 import re
 import sys
 import urllib
 
@@ skipping 118 matching lines @@
 
     Returns:
       The possible browser if found, or None otherwise.
     """
     possible_browser = browser_finder.FindBrowser(options)
     if possible_browser is None:
       return None
 
     if self._platform is None:
       self._platform = possible_browser.platform
+      # TODO(nedn): Remove the if condition once
+      # https://codereview.chromium.org/2265593003/ is rolled to Chromium tree.
+      if hasattr(self._platform.network_controller, 'InitializeIfNeeded'):
+        self._platform.network_controller.InitializeIfNeeded()
     else:
       assert self._platform is possible_browser.platform
     self._possible_browsers[browser_type] = (possible_browser, options)
     return possible_browser
 
   def _CreateAllBrowsersIfNeeeded(self):
     """Launch all browsers needed for the story set, if not already done.
 
     This ensures that all browsers are alive during the whole duration of the
     benchmark and, therefore, e.g. memory dumps are always provided for all
@@ skipping 109 matching lines @@
           url=GOOGLE_SEARCH + urllib.urlencode({'q': query}),
           browser_type='android-webview',
           phase='on_webview'))
 
       # Stories that run on the browser selected by command line options.
       self.AddStory(SinglePage(
           name=re.sub(r'\W+', '_', url),
           url=url,
           browser_type='default',
           phase='on_chrome'))