Update from https://crrev.com/306655

sandbox/linux/sandbox_linux.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.
 
 {
   'variables': {
     'conditions': [
       ['OS=="linux"', {
         'compile_suid_client': 1,
         'compile_credentials': 1,
@@ skipping 216 matching lines @@
         'services/syscall_wrappers.h',
         'services/thread_helpers.cc',
         'services/thread_helpers.h',
         'services/yama.cc',
         'services/yama.h',
         'syscall_broker/broker_channel.cc',
         'syscall_broker/broker_channel.h',
         'syscall_broker/broker_client.cc',
         'syscall_broker/broker_client.h',
         'syscall_broker/broker_common.h',
+        'syscall_broker/broker_file_permission.cc',
+        'syscall_broker/broker_file_permission.h',
         'syscall_broker/broker_host.cc',
         'syscall_broker/broker_host.h',
         'syscall_broker/broker_policy.cc',
         'syscall_broker/broker_policy.h',
         'syscall_broker/broker_process.cc',
         'syscall_broker/broker_process.h',
       ],
       'dependencies': [
         '../base/base.gyp:base',
       ],
       'defines': [
         'SANDBOX_IMPLEMENTATION',
       ],
       'conditions': [
         ['compile_credentials==1', {
           'sources': [
             'services/credentials.cc',
             'services/credentials.h',
+            'services/proc_util.cc',
+            'services/proc_util.h',
           ],
           'dependencies': [
             # for capabilities.cc.
             '../build/linux/system.gyp:libcap',
           ],
         }],
       ],
       'include_dirs': [
         '..',
       ],
@@ skipping 115 matching lines @@
             '../../build/isolate.gypi',
           ],
           'sources': [
             '../sandbox_linux_unittests.isolate',
           ],
         },
       ],
     }],
   ],
 }