Allow building mojo_shell and non-graphical apps/services on a Mac

mojo/dart/embedder/BUILD.gn

 # 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.
 
 # embedder specific template rules.
 import("embedder.gni")
 
 source_set("dart_controller_no_snapshot") {
   sources = [
     "$target_gen_dir/dart_embedder_patch_resources.cc",
     "$target_gen_dir/dart_embedder_service_isolate_resources.cc",
     "builtin.cc",
     "builtin.h",
     "builtin_natives.cc",
     "common.cc",
     "common.h",
     "dart_controller.cc",
     "dart_controller.h",
     "io/internet_address.h",
+    "io/internet_address_posix.cc",
     "mojo_dart_state.h",
     "mojo_io_natives.cc",
     "mojo_io_natives.h",
     "mojo_natives.cc",
     "mojo_natives.h",
     "vmservice.cc",
     "vmservice.h",
   ]
 
-  if (is_linux) {
-    sources += [ "io/internet_address_linux.cc" ]
-  }
-
-  if (is_android) {
-    sources += [ "io/internet_address_android.cc" ]
-  }
-
   deps = [
     ":dart_embedder_packages",
     ":generate_dart_embedder_patch_resources_cc",
     ":generate_dart_embedder_service_isolate_resources_cc",
     "//base",
     "//base:i18n",
     "//dart/runtime:libdart",
     "//dart/runtime/bin:libdart_embedder_noio",
     "//third_party/dart-pkg",
     "//mojo/message_pump",
@@ skipping 366 matching lines @@
 
 source_set("dart_snapshot_cc") {
   sources = [
     "$root_gen_dir/dart_snapshot.cc",
   ]
 
   deps = [
     ":generate_snapshot_file",
   ]
 }