Move test_service implementation to //services

services/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.
 
 import("//build/config/ui.gni")
 
 group("services") {
   deps = [
     "//services/clipboard",
     "//services/http_server",
     "//services/http_server/public",
     "//services/js",
     "//services/surfaces",
+    "//services/test_service:bindings",
     "//services/tracing",
   ]
 
   if (use_aura) {
     deps += [
       "//services/view_manager",
       "//services/window_manager",
     ]
   }
 }