Add test infrastructure for the file-picker modal test

chrome/chrome_tests.gypi

 # 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.
 {
   'variables': {
     'chrome_browser_extensions_test_support_sources': [
       # A list of sources which is shared between different browser tests.
       'browser/apps/app_browsertest_util.cc',
       'browser/apps/app_browsertest_util.h',
       'browser/extensions/browsertest_util.cc',
@@ skipping 1676 matching lines @@
         }],
         ['OS=="linux" and chromeos==0', {
           'sources!': [
             # TODO(port): This times out. Attempts have been made to fix the
             # individual failures, but each time I disable a test from these
             # suites, it seems like one or another starts timing out too.
 
             # Note: list duplicated in GN build.
             'browser/ui/views/keyboard_access_browsertest.cc',
           ],
+          'sources': [ 'browser/ui/libgtk2ui/select_file_dialog_interactive_uitest.cc' ],
+          'dependencies': [ '../build/linux/system.gyp:gtk2' ],
         }, {  # Everything but desktop Linux.
           'sources': [ '<@(chrome_interactive_ui_test_non_desktop_linux_sources)' ],
         }],
         ['use_ash==1', {
           'sources': [ '<@(chrome_interactive_ui_test_ash_sources)' ],
           'dependencies': [
             '../ash/ash.gyp:ash_interactive_ui_test_support',
           ],
         }],
         ['OS=="mac"', {
@@ skipping 1777 matching lines @@
             'utility',
           ],
           'sources': [
             'tools/service_discovery_sniffer/service_discovery_sniffer.cc',
             'tools/service_discovery_sniffer/service_discovery_sniffer.h',
           ],
         }]
     }],
   ],  # 'conditions'
 }