Introduce chrome.displaySource API

extensions/extensions_tests.gypi

 # Copyright 2015 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': {
     'extensions_browsertests_sources': [
       'browser/api/audio/audio_apitest.cc',
       'browser/api/bluetooth_socket/bluetooth_socket_apitest.cc',
+      'browser/api/display_source/display_source_apitest.cc',
       'browser/api/dns/dns_apitest.cc',
       'browser/api/hid/hid_apitest.cc',
       'browser/api/printer_provider/printer_provider_apitest.cc',
       'browser/api/socket/socket_apitest.cc',
       'browser/api/sockets_tcp/sockets_tcp_apitest.cc',
       'browser/api/sockets_tcp_server/sockets_tcp_server_apitest.cc',
       'browser/api/sockets_udp/sockets_udp_apitest.cc',
       'browser/api/system_cpu/system_cpu_apitest.cc',
       'browser/api/system_display/system_display_apitest.cc',
       'browser/api/system_memory/system_memory_apitest.cc',
@@ skipping 141 matching lines @@
       'renderer/scoped_web_frame.h',
       'renderer/script_context_set_unittest.cc',
       'renderer/script_context_unittest.cc',
       'renderer/utils_unittest.cc',
       'shell/browser/shell_web_contents_modal_dialog_manager.cc',
       'test/extensions_unittests_main.cc',
       'utility/unpacker_unittest.cc',
     ],
   },
 }