Create a RegisterViewAssociate method in ViewManager

services/ui/view_manager/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("//testing/test.gni")
 
 mojo_native_application("view_manager") {
   output_name = "view_manager_service"
 
@@ skipping 29 matching lines @@
     "//mojo/converters/geometry",
     "//mojo/environment:chromium",
     "//mojo/public/cpp/bindings:bindings",
     "//mojo/services/geometry/cpp",
     "//mojo/services/gfx/composition/cpp",
     "//mojo/services/gfx/composition/interfaces",
     "//mojo/services/ui/views/cpp",
     "//mojo/services/ui/views/interfaces",
   ]
 }
+
+mojo_native_application("view_manager_apptests") {
+  output_name = "view_manager_apptests"
+
+  testonly = true
+
+  sources = [
+    "tests/view_manager_test.cc",
+  ]
+
+  deps = [
+    "//base",
+    "//mojo/application",
+    "//mojo/application:test_support",
+    "//mojo/common",
+    "//mojo/common:tracing_impl",
+    "//mojo/converters/geometry",
+    "//mojo/environment:chromium",
+    "//mojo/public/cpp/bindings",
+    "//mojo/public/cpp/bindings:bindings",
+    "//mojo/services/geometry/cpp",
+    "//mojo/services/gfx/composition/cpp",
+    "//mojo/services/gfx/composition/interfaces",
+    "//mojo/services/ui/views/cpp",
+    "//mojo/services/ui/views/interfaces",
+  ]
+}