Add client for background testing of HTTP pipelining.

chrome/chrome_tests.gypi

 # Copyright (c) 2012 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.
 {
   'variables' : {
     'pyautolib_sources': [
       'app/chrome_command_ids.h',
       'app/chrome_dll_resource.h',
       'common/automation_constants.h',
       'common/pref_names.cc',
@@ skipping 1513 matching lines @@
         'browser/metrics/metrics_response_unittest.cc',
         'browser/metrics/metrics_service_unittest.cc',
         'browser/metrics/thread_watcher_unittest.cc',
         'browser/mock_keychain_mac.cc',
         'browser/mock_keychain_mac.h',
         'browser/net/browser_url_util_unittest.cc',
         'browser/net/chrome_fraudulent_certificate_reporter_unittest.cc',
         'browser/net/chrome_net_log_unittest.cc',
         'browser/net/connection_tester_unittest.cc',
         'browser/net/gaia/gaia_oauth_fetcher_unittest.cc',
+        'browser/net/http_pipelining_compatibility_client_unittest.cc',
         'browser/net/http_server_properties_manager_unittest.cc',
         'browser/net/load_timing_observer_unittest.cc',
         'browser/net/network_stats_unittest.cc',
         'browser/net/passive_log_collector_unittest.cc',
         'browser/net/predictor_unittest.cc',
         'browser/net/pref_proxy_config_tracker_impl_unittest.cc',
         'browser/net/quoted_printable_unittest.cc',
         'browser/net/sqlite_origin_bound_cert_store_unittest.cc',
         'browser/net/sqlite_persistent_cookie_store_unittest.cc',
         'browser/net/ssl_config_service_manager_pref_unittest.cc',
@@ skipping 3105 matching lines @@
               # Use outputs of this action as inputs for the main target build.
               # Seems as a misnomer but makes this happy on Linux (scons).
               'process_outputs_as_sources': 1,
             },
           ],  # 'actions'
         },
       ]
     }],  # 'coverage!=0'
   ],  # 'conditions'
 }