Add chrome.usbPrivate API for use by USB device WEBUI.

extensions/extensions.gyp

 # 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': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 352 matching lines @@
         'browser/api/storage/value_store_cache.cc',
         'browser/api/storage/value_store_cache.h',
         'browser/api/storage/weak_unlimited_settings_storage.cc',
         'browser/api/storage/weak_unlimited_settings_storage.h',
         'browser/api/test/test_api.cc',
         'browser/api/test/test_api.h',
         'browser/api/usb/usb_api.cc',
         'browser/api/usb/usb_api.h',
         'browser/api/usb/usb_device_resource.cc',
         'browser/api/usb/usb_device_resource.h',
+        'browser/api/usb_private/usb_private_api.cc',
+        'browser/api/usb_private/usb_private_api.h',
         'browser/api_activity_monitor.h',
         'browser/app_sorting.h',
         'browser/blacklist_state.h',
         'browser/blob_holder.cc',
         'browser/blob_holder.h',
         'browser/browser_context_keyed_api_factory.h',
         'browser/browser_context_keyed_service_factories.cc',
         'browser/browser_context_keyed_service_factories.h',
         'browser/component_extension_resource_manager.h',
         'browser/computed_hashes.cc',
@@ skipping 532 matching lines @@
           'browser/api/cast_channel/logging.proto'
       ],
       'variables': {
           'proto_in_dir': 'browser/api/cast_channel',
           'proto_out_dir': 'extensions/browser/api/cast_channel',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ]
 }