Don't compile in root certs when SSL is disabled in GN build.

runtime/bin/BUILD.gn

 # Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 
 declare_args() {
   dart_io_support = false
 }
 
 
@@ skipping 220 matching lines @@
 source_set("gen_snapshot_dart_io") {
   configs += ["..:dart_config",]
 
   # Set custom sources assignment filter. The custom filters does three things:
   # 1) Filters out unnecessary files pulled in from the gypi files.
   # 2) Filters out secure socket support.
   # 3) Enables dart:io by filtering out _unsupported.cc implementations.
   custom_sources_filter = [
     "*net/nss_memio.cc",
     "*net/nss_memio.h",
+    "*root_certificates.cc",
     "*secure_socket.cc",
     "*secure_socket.h",
     "filter.cc",
     "*io_service_unsupported.cc",
     "platform_*.cc",
     "*io_service.cc",
     "*io_service.h",
     "*_test.cc",
     "*_test.h",
     "*dbg*",
@@ skipping 34 matching lines @@
 source_set("embedded_dart_io") {
   configs += ["..:dart_config",]
 
   # Set custom sources assignment filter. The custom filters does three things:
   # 1) Filters out unnecessary files pulled in from the gypi files.
   # 2) Filters out secure socket support.
   # 3) Enables dart:io by filtering out _unsupported.cc implementations.
   custom_sources_filter = [
     "*net/nss_memio.cc",
     "*net/nss_memio.h",
+    "*root_certificates.cc",
     "*secure_socket.cc",
     "*secure_socket.h",
     "*filter_unsupported.cc",
     "*io_service_unsupported.cc",
     "*io_service.cc",
     "*io_service.h",
     "*_test.cc",
     "*_test.h",
     "*dbg*",
     "builtin.cc",
@@ skipping 23 matching lines @@
     "log_macos.cc",
     "log_win.cc",
     "log.h",
   ]
 
   include_dirs = [
     "..",
     "//third_party"
   ]
 }