Build libraries for a number of services.

services/ui/launcher/BUILD.gn

 # Copyright 2015 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("//mojo/public/mojo_application.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 import("//testing/test.gni")
 
 mojo_native_application("launcher") {
   sources = [
+    "main.cc",
+  ]
+
+  deps = [
+    ":lib",
+    "//mojo/application",
+  ]
+}
+
+source_set("lib") {
+  sources = [
     "launch_instance.cc",
     "launch_instance.h",
     "launcher_app.cc",
     "launcher_app.h",
     "launcher_view_tree.cc",
     "launcher_view_tree.h",
-    "main.cc",
   ]
 
   deps = [
     ":bindings",
     "//base",
     "//mojo/application",
     "//mojo/common",
     "//mojo/common:tracing_impl",
     "//mojo/environment:chromium",
     "//mojo/public/cpp/bindings:bindings",
     "//mojo/services/gfx/composition/cpp",
     "//mojo/services/gfx/composition/interfaces",
     "//mojo/services/native_viewport/interfaces",
     "//mojo/services/ui/input/interfaces",
     "//mojo/services/ui/views/cpp",
     "//mojo/services/ui/views/interfaces",
   ]
 }
 
 mojom("bindings") {
   sources = [
     "launcher.mojom",
   ]
 }