Use BookmarkAppConfirmationView on Mac. Delete the NSAlert Mac uses currently.

chrome/test/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/chrome_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//chrome/common/features.gni")
@@ skipping 1949 matching lines @@
         if (enable_nacl_nonsfi) {
           data_deps += [ "//components/nacl/loader:helper_nonsfi" ]
         }
       }
     }
 
     if (enable_extensions) {
       sources += [
         "../browser/apps/app_browsertest_util.cc",
         "../browser/apps/app_browsertest_util.h",
+        "../browser/extensions/bookmark_app_helper_browsertest.cc",
         "../browser/extensions/browsertest_util.cc",
         "../browser/extensions/browsertest_util.h",
         "../browser/extensions/extension_apitest.cc",
         "../browser/extensions/extension_apitest.h",
         "../browser/extensions/extension_browsertest.cc",
         "../browser/extensions/extension_browsertest.h",
         "../browser/extensions/extension_function_test_utils.cc",
         "../browser/extensions/extension_function_test_utils.h",
         "../browser/extensions/extension_with_management_policy_apitest.cc",
         "../browser/extensions/extension_with_management_policy_apitest.h",
@@ skipping 3162 matching lines @@
 }
 
 if (is_win) {
   loadable_module("conflicts_dll") {
     testonly = true
     sources = [
       "conflicts/conflicts_dll.cc",
     ]
   }
 }