Adding libusb as a direct dependency of browser_extensions.

chrome/chrome_browser_extensions.gypi

 # Copyright (c) 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.
 
 {
   'targets': [
     {
       'target_name': 'browser_extensions',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 13 matching lines @@
         'installer_util',
         '../build/temp_gyp/googleurl.gyp:googleurl',
         '../content/content.gyp:content_browser',
         '../crypto/crypto.gyp:crypto',
         '../net/net.gyp:net',
         '../skia/skia.gyp:skia',
         '../third_party/bzip2/bzip2.gyp:bzip2',
         '../third_party/icu/icu.gyp:icui18n',
         '../third_party/icu/icu.gyp:icuuc',
         '../third_party/leveldatabase/leveldatabase.gyp:leveldatabase',
+        '../third_party/libusb/libusb.gyp:libusb',
         '../ui/base/strings/ui_strings.gyp:ui_strings',
         '../ui/ui.gyp:ui',
         '../ui/ui.gyp:ui_resources',
         '../ui/ui.gyp:ui_resources_2x',
         '../ui/ui.gyp:ui_resources_standard',
         '../webkit/support/webkit_support.gyp:appcache',
         '../webkit/support/webkit_support.gyp:blob',
         '../webkit/support/webkit_support.gyp:database',
         '../webkit/support/webkit_support.gyp:fileapi',
         '../webkit/support/webkit_support.gyp:glue',
@@ skipping 606 matching lines @@
             'browser/extensions/api/usb/usb_api.h',
             'browser/extensions/api/usb/usb_device_resource.cc',
             'browser/extensions/api/usb/usb_device_resource.h',
           ],
         }],
       ],
     },
   ],
 }