Adding use_system_libusb option for third_party/libusb

tools/checklicenses/checklicenses.py

 #!/usr/bin/env python
 # 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.
 
 """Makes sure that all files contain proper licensing information."""
 
 
 import optparse
 import os.path
@@ skipping 227 matching lines @@
         'UNKNOWN',
     ],
     'third_party/libjpeg_turbo': [  # http://crbug.com/98314
         'UNKNOWN',
     ],
     'third_party/libpng': [  # http://crbug.com/98318
         'UNKNOWN',
     ],
 
     # The following files lack license headers, but are trivial.
-    'third_party/libusb/libusb/os/poll_posix.h': [
+    'third_party/libusb/src/libusb/os/poll_posix.h': [
         'UNKNOWN',
     ],
-    'third_party/libusb/libusb/version.h': [
+    'third_party/libusb/src/libusb/version.h': [
         'UNKNOWN',
     ],
-    'third_party/libusb/autogen.sh': [
+    'third_party/libusb/src/autogen.sh': [
         'UNKNOWN',
     ],
-    'third_party/libusb/config.h': [
+    'third_party/libusb/src/config.h': [
         'UNKNOWN',
     ],
-    'third_party/libusb/msvc/config.h': [
+    'third_party/libusb/src/msvc/config.h': [
         'UNKNOWN',
     ],
 
     # The package has a compatible COPYING file and most source files conform,
     # but there are several exceptions.
     # TODO(posciak,fischman): remove this exception once upstream makes all
     # their files conform.  https://bugs.freedesktop.org/show_bug.cgi?id=49588
     # http://crbug.com/126466
     'third_party/libva/va/va_x11.h': [
         'UNKNOWN',
@@ skipping 266 matching lines @@
   option_parser.add_option('--ignore-suppressions',
                            action='store_true',
                            default=False,
                            help='Ignore path-specific license whitelist.')
   options, args = option_parser.parse_args()
   return check_licenses(options, args)
 
 
 if '__main__' == __name__:
   sys.exit(main())