Update from https://crrev.com/316786

third_party/fontconfig/fontconfig.gyp

 # Copyright 2014 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': 'fontconfig',
       'type': '<(component)',
       'dependencies' : [
         '../zlib/zlib.gyp:zlib',
         '../../build/linux/system.gyp:freetype2',
         '../libxml/libxml.gyp:libxml',
       ],
       'defines': [
           'HAVE_CONFIG_H',
           'FC_CACHEDIR="/var/cache/fontconfig"',
           'FONTCONFIG_PATH="/etc/fonts"',
       ],
       'conditions': [
         ['clang==1', {
           # Work around a null-conversion warning. See crbug.com/358852.
           'cflags': [
             '-Wno-non-literal-null-conversion',
           ],
         }],
       ],
       'sources': [
+        'chromium/empty.cc',
         'src/src/fcarch.h',
         'src/src/fcatomic.c',
         'src/src/fcblanks.c',
         'src/src/fccache.c',
         'src/src/fccfg.c',
         'src/src/fccharset.c',
         'src/src/fccompat.c',
         'src/src/fcdbg.c',
         'src/src/fcdefault.c',
         'src/src/fcdir.c',
@@ skipping 22 matching lines @@
         'include/src',
       ],
       'direct_dependent_settings': {
         'include_dirs': [
            'src',
         ],
       },
     },
   ],
 }