Add chrome test support target to GN build.

chrome/browser/ui/BUILD.gn

 # Copyright 2014 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("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 
 gypi_values = exec_script(
     "//build/gypi_to_gn.py",
@@ skipping 403 matching lines @@
     script = "//chrome/tools/build/mac/generate_localizer"
     sources = [ ]
     table_path = "$target_gen_dir/ui_localizer_table.h"
     outputs = [ table_path ]
     args = [ rebase_path(table_path, root_build_dir) ] +
              rebase_path(nib_gypi_values.mac_translated_xibs,
                          root_build_dir,
                          "//chrome")
   }
 }
+
+# In GYP this is part of test_support_common.
+source_set("test_support") {
+  testonly = true
+
+  sources = [
+    "browser.h",
+    "cocoa/find_bar/find_bar_host_unittest_util_cocoa.mm",
+    "cocoa/run_loop_testing.h",
+    "cocoa/run_loop_testing.mm",
+    "find_bar/find_bar_host_unittest_util.h",
+    "fullscreen/fullscreen_controller_state_test.cc",
+    "fullscreen/fullscreen_controller_state_test.h",
+    "fullscreen/fullscreen_controller_state_tests.h",
+    "fullscreen/fullscreen_controller_test.cc",
+    "fullscreen/fullscreen_controller_test.h",
+    "login/login_prompt_test_utils.cc",
+    "login/login_prompt_test_utils.h",
+    "passwords/manage_passwords_ui_controller_mock.cc",
+    "passwords/manage_passwords_ui_controller_mock.h",
+    "pdf/pdf_browsertest_base.cc",
+    "pdf/pdf_browsertest_base.h",
+    "test/test_confirm_bubble_model.cc",
+    "test/test_confirm_bubble_model.h",
+    "views/find_bar_host_unittest_util_views.cc",
+    "website_settings/mock_permission_bubble_request.cc",
+    "website_settings/mock_permission_bubble_request.h",
+  ]
+
+  deps = [
+    ":ui",
+    "//chrome/app/theme:theme_resources",
+    "//chrome/browser",
+    "//content/public/browser",
+    "//content/public/common",
+    "//content/test:test_support",
+    "//net:test_support",
+    "//skia",
+    "//testing/gtest",
+    "//ui/base",
+  ]
+
+  forward_dependent_configs_from = [
+    ":ui",
+  ]
+}