Fix "Set pages" drop crash by changing outside drags to simply add a new URL

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' : {
     'chromedriver_unittest_sources': [
       'test/chromedriver/capabilities_unittest.cc',
       'test/chromedriver/chrome/chrome_finder_unittest.cc',
       'test/chromedriver/chrome/console_logger_unittest.cc',
       'test/chromedriver/chrome/device_manager_unittest.cc',
@@ skipping 1492 matching lines @@
         'browser/ui/webui/options/options_browsertest.js',
         'browser/ui/webui/options/options_ui_browsertest.cc',
         'browser/ui/webui/options/options_ui_browsertest.h',
         'browser/ui/webui/options/password_manager_browsertest.js',
         'browser/ui/webui/options/profile_settings_reset_browsertest.js',
         'browser/ui/webui/options/preferences_browsertest.cc',
         'browser/ui/webui/options/preferences_browsertest.h',
         'browser/ui/webui/options/search_engine_manager_browsertest.js',
         'browser/ui/webui/options/settings_app_browsertest.js',
         'browser/ui/webui/options/settings_format_browsertest.js',
+        'browser/ui/webui/options/startup_page_list_browsertest.js',
         'browser/ui/webui/policy_ui_browsertest.cc',
         'browser/ui/webui/print_preview/print_preview_ui_browsertest.cc',
         'browser/ui/webui/signin/user_manager_ui_browsertest.cc',
         'browser/ui/webui/sync_setup_browsertest.js',
         'browser/ui/webui/web_ui_test_handler.cc',
         'browser/ui/webui/web_ui_test_handler.h',
         'browser/user_data_dir_extractor_win_browsertest.cc',
         'browser/unload_browsertest.cc',
         'common/mac/mock_launchd.cc',
         'common/mac/mock_launchd.h',
@@ skipping 1698 matching lines @@
             'utility',
           ],
           'sources': [
             'tools/service_discovery_sniffer/service_discovery_sniffer.h',
             'tools/service_discovery_sniffer/service_discovery_sniffer.cc',
           ],
         }]
     }],
   ],  # 'conditions'
 }