Make udev target disappear on linux when use_udev==0

third_party/libusb/libusb.gyp

 # 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': 'libusb',
       'type': 'static_library',
       'sources': [
@@ skipping 35 matching lines @@
             'HAVE_GETTIMEOFDAY=1',
             'HAVE_POLL_H=1',
             'HAVE_SYS_TIME_H=1',
             'LIBUSB_DESCRIBE="1.0.16"',
             'POLL_NFDS_TYPE=nfds_t',
             'THREADS_POSIX=1',
           ],
         }],
         [ 'OS == "linux" or OS == "android"', {
           'sources': [
-            'src/libusb/os/linux_udev.c',
             'src/libusb/os/linux_usbfs.c',
             'src/libusb/os/linux_usbfs.h',
           ],
           'defines': [
+            'OS_LINUX=1',
+            '_GNU_SOURCE=1',
+          ],
+        }],
+        [ 'use_udev == 1 or OS == "android"', {
+          'sources': [
+            'src/libusb/os/linux_udev.c',
+          ],
+          'defines': [
             'HAVE_LIBUDEV=1',
-            'OS_LINUX=1',
             'USE_UDEV=1',
-            '_GNU_SOURCE=1',
+          ],
+        }],
+        [ 'OS == "linux" and use_udev == 0', {
+          'sources': [
+            'src/libusb/os/linux_netlink.c',
+          ],
+          'defines': [
+            'HAVE_LINUX_NETLINK_H',
+          ],
+          'conditions': [
+            ['clang==1', {
+              'cflags': [
+                '-Wno-pointer-sign',
+              ]
+            }]
           ],
         }],
         [ 'OS == "mac"', {
           'sources': [
             'src/libusb/os/darwin_usb.c',
             'src/libusb/os/darwin_usb.h',
           ],
           'defines': [
             'OS_DARWIN=1',
           ],
@@ skipping 16 matching lines @@
           ],
           'include_dirs': [
             'src/msvc',
           ],
           'msvs_disabled_warnings': [ 4267 ],
         }],
       ],
     },
   ],
 }