Revert of Build services as standalone executables

services/service_manager/runner/BUILD.gn

 # Copyright 2016 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.
 
 group("runner") {
   testonly = true
   deps = [
+    "//services/service_manager/runner/child",
     "//services/service_manager/runner/host",
   ]
 }
 
 source_set("init") {
   sources = [
     "init.cc",
     "init.h",
   ]
 
   deps = [
     "//base",
     "//base:base_static",
     "//base:i18n",
     "//services/service_manager/runner/common",
   ]
 }