Add Mojo IPC based input-device service.

components/mus/public/cpp/input_devices/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.
 
-component("init") {
-  output_name = "gl_init"
-
+source_set("input_devices") {
   sources = [
-    "gl_factory.cc",
-    "gl_factory.h",
-    "gl_init_export.h",
+    "input_device_client.h",
+    "lib/input_device_client.cc",
   ]
-  defines = [ "GL_INIT_IMPLEMENTATION" ]
 
   deps = [
     "//base",
-    "//ui/gfx",
+    "//services/shell/public/cpp:sources",
+    "//skia",
+    "//ui/events/devices",
   ]
 
   public_deps = [
-    "//ui/gl",
+    "//components/mus/public/interfaces/input_devices",
   ]
 }