Remove Chrome OS-related GN build configuration

build/config/features.gni

 # 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.
 
 # This file contains Chrome-feature-related build flags (see ui.gni for
 # UI-related ones). These should theoretically be moved to the build files of
 # the features themselves.
 #
 # However, today we have many "bad" dependencies on some of these flags from,
 # e.g. base, so they need to be global to match the GYP configuration. Also,
@@ skipping 13 matching lines @@
   # TODO(GYP): Get NaCl linking on other platforms.
   # Also, see if we can always get rid of enable_nacl_untrusted and
   # enable_pnacl and always build them if enable_nacl is true.
   # The "is_nacl" part of the condition is needed to ensure that
   # the untrusted code is built properly; arguably it should be
   # guarded by "is_nacl" directly rather than enable_nacl_untrusted, but
   # this will go away when Mac and Win are working and we can just use
   # the commented out logic.
   # Eventually we want this to be:
   #   enable_nacl = !is_ios && !is_android
-  enable_nacl = (is_linux && !is_chromeos && current_cpu == "x64") || is_nacl
+  enable_nacl = (is_linux && current_cpu == "x64") || is_nacl
   enable_nacl_untrusted = enable_nacl
   enable_pnacl = enable_nacl_untrusted
 }
 
 # Additional dependent variables -----------------------------------------------
 
 # Set the version of CLD.
 #   0: Don't specify the version. This option is for the Finch testing.
 #   1: Use only CLD1.
 #   2: Use only CLD2.
 if (is_android) {
   cld_version = 1
 } else {
   cld_version = 2
 }
 
 # libudev usage.
 use_udev = is_linux && !is_fnl
 
 # The seccomp-bpf sandbox is only supported on three architectures
 # currently.
 # Do not disable seccomp_bpf anywhere without talking to
 # security@chromium.org!
 use_seccomp_bpf = (is_linux || is_android) &&
                   (current_cpu == "x86" || current_cpu == "x64" ||
                    current_cpu == "arm" || current_cpu == "mipsel")