[Telemetry] Use --ignore-certificate-errors-spki-list to bypass cert errors

telemetry/telemetry/internal/backends/chrome/chrome_browser_backend.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 logging
+import os
 import pprint
 import shlex
 import sys
 
 from telemetry.core import exceptions
 from telemetry.core import util
 from telemetry import decorators
 from telemetry.internal.backends import browser_backend
 from telemetry.internal.backends.chrome import extension_backend
 from telemetry.internal.backends.chrome import tab_list_backend
@@ skipping 105 matching lines @@
     return args
 
   def GetReplayBrowserStartupArgs(self):
     replay_args = []
     network_backend = self.platform_backend.network_controller_backend
     if not network_backend.is_initialized:
       return []
     proxy_port = network_backend.forwarder.port_pair.remote_port
     replay_args.append('--proxy-server=socks://localhost:%s' % proxy_port)
     if not network_backend.is_test_ca_installed:
-      # Ignore certificate errors if the platform backend has not created
-      # and installed a root certificate.
-      replay_args.append('--ignore-certificate-errors')
+      # Ignore certificate errors for certs that are signed with Wpr's root.
+      # For more details on this flag, see crbug.com/753948.
+      wpr_public_hash_file = os.path.join(util.GetCatapultDir(),
+                                          'web_page_replay_go',
+                                          'wpr_public_hash.txt')
+      if not os.path.exists(wpr_public_hash_file):
+        raise exceptions.PathMissingError('Unable to find %s' %
+                                          wpr_public_hash_file)
+      with open(wpr_public_hash_file) as f:
+        wpr_public_hash = f.readline().strip()
+        replay_args.append('--ignore-certificate-errors-spki-list=' +
+                           wpr_public_hash)
     return replay_args
 
   def HasBrowserFinishedLaunching(self):
     assert self._port, 'No DevTools port info available.'
     return devtools_client_backend.IsDevToolsAgentAvailable(
         self._port,
         self._browser_target, self)
 
   def _WaitForBrowserToComeUp(self, remote_devtools_port=None):
     """ Wait for browser to come up.
@@ skipping 160 matching lines @@
   def supports_cpu_metrics(self):
     return True
 
   @property
   def supports_memory_metrics(self):
     return True
 
   @property
   def supports_power_metrics(self):
     return True