Implement net in GN build.

base/BUILD.gn

 # Copyright (c) 2013 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.
 
 import("//build/config/ui.gni")
 
 component("base") {
   sources = [
     "third_party/dmg_fp/dmg_fp.h",
     "third_party/dmg_fp/g_fmt.cc",
@@ skipping 713 matching lines @@
   ]
 
   deps = [
     ":base_static",
     "//base/allocator:allocator_extension_thunks",
     "//base/third_party/dynamic_annotations",
     "//base/third_party/nspr",
     "//third_party/modp_b64",
   ]
 
-  if (!is_chromeos) {
-    sources -= [
-      "sys_info_chromeos.cc",
-    ]
-  }
-
   if (is_nacl) {
     # These things would otherwise be built on a Posix build but aren't
     # supported on NaCl.
     sources -= [
       "debug/stack_trace_posix.cc",
       "files/file_enumerator_posix.cc",
       "file_util_posix.cc",
       "message_loop/message_pump_libevent.cc",
       "process/kill_posix.cc",
       "process/launch_posix.cc",
@@ skipping 156 matching lines @@
   #    # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
   #    'msvs_disabled_warnings': [
   #      4267,
   #    ],
   #  }],
   #],
   #'variables': {
   #  'optimize': 'max',
   #},
 }