[sync]sync_integration_tests using python server fail

components/sync/test/local_sync_test_server.cc

 // 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.
 
 #include "components/sync/test/local_sync_test_server.h"
 
 #include <stdint.h>
 
 #include <string>
 
@@ skipping 19 matching lines @@
           net::SpawnedTestServer::kLocalhost,
           base::FilePath()),
       xmpp_port_(xmpp_port) {
   SetPort(port);
 }
 
 LocalSyncTestServer::~LocalSyncTestServer() {}
 
 bool LocalSyncTestServer::AddCommandLineArguments(
     base::CommandLine* command_line) const {
+  // Suppress loading of site packages in order to avoid a version mismatch
+  // between pre-installed versions of python libraries.
+  // See https://bugs.chromium.org/p/chromium/issues/detail?id=649829
+  command_line->AppendSwitch("-S");
   if (!LocalTestServer::AddCommandLineArguments(command_line))
     return false;
   if (xmpp_port_ != 0) {
     std::string xmpp_port_str = base::UintToString(xmpp_port_);
     command_line->AppendArg("--xmpp-port=" + xmpp_port_str);
   }
   return true;
 }
 
 bool LocalSyncTestServer::GetTestServerPath(
@@ skipping 43 matching lines @@
                  << "Testserver features that rely on it will not work";
     return true;
   }
   AppendToPythonPath(pyproto_dir.AppendASCII("components")
                          .AppendASCII("sync")
                          .AppendASCII("protocol"));
   return true;
 }
 
 }  // namespace syncer