Add chrome://usb-internals page for adding and removing test devices.

chrome/chrome_browser_ui.gypi

 # Copyright 2012 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': {
     # There are two sections of sources:
     # * "Platform"-based sources (OS, toolkit, etc.)
     # * Feature/directory-based sources (e.g., history, printing)
 
@@ skipping 367 matching lines @@
       'browser/ui/webui/sync_internals_ui.cc',
       'browser/ui/webui/sync_internals_ui.h',
       'browser/ui/webui/test_files_request_filter.cc',
       'browser/ui/webui/test_files_request_filter.h',
       'browser/ui/webui/theme_source.cc',
       'browser/ui/webui/theme_source.h',
       'browser/ui/webui/translate_internals/translate_internals_handler.cc',
       'browser/ui/webui/translate_internals/translate_internals_handler.h',
       'browser/ui/webui/translate_internals/translate_internals_ui.cc',
       'browser/ui/webui/translate_internals/translate_internals_ui.h',
+      'browser/ui/webui/usb_internals/usb_internals_page_handler.cc',
+      'browser/ui/webui/usb_internals/usb_internals_page_handler.h',
+      'browser/ui/webui/usb_internals/usb_internals_ui.cc',
+      'browser/ui/webui/usb_internals/usb_internals_ui.h',
       'browser/ui/webui/user_actions/user_actions_ui.cc',
       'browser/ui/webui/user_actions/user_actions_ui.h',
       'browser/ui/webui/user_actions/user_actions_ui_handler.cc',
       'browser/ui/webui/user_actions/user_actions_ui_handler.h',
       'browser/ui/webui/version_handler.cc',
       'browser/ui/webui/version_handler.h',
       'browser/ui/webui/version_handler_chromeos.cc',
       'browser/ui/webui/version_handler_chromeos.h',
       'browser/ui/webui/version_ui.cc',
       'browser/ui/webui/version_ui.h',
@@ skipping 2968 matching lines @@
           ],
           'sources': [
             '<@(chrome_browser_ui_non_mobile_sources)',
             '<@(chrome_browser_ui_omnibox_non_mobile_sources)',
           ],
         }],
       ],
     },
   ],
 }