Add the beginning of a simple window manager that we'll support on Windows.

mash/simple_wm/BUILD.gn

Index: mash/simple_wm/BUILD.gn
diff --git a/mash/simple_wm/BUILD.gn b/mash/simple_wm/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..2145fde745df4d2fd2fa1bc0e1e9ca53c8862b8c
--- /dev/null
+++ b/mash/simple_wm/BUILD.gn
@@ -0,0 +1,62 @@
+# 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.
+
+import("//build/config/ui.gni")
+import("//services/service_manager/public/cpp/service.gni")
+import("//services/service_manager/public/service_manifest.gni")
+import("//tools/grit/repack.gni")
+
+service("simple_wm") {
+  testonly = true
+
+  sources = [
+    "main.cc",
+  ]
+
+  deps = [
+    ":lib",
+    "//base",
+    "//services/service_manager/public/cpp",
+    "//ui/views/mus:for_mojo_application",
+  ]
+
+  resources = [ "$root_out_dir/views_mus_resources.pak" ]
+}
+
+source_set("lib") {
+  testonly = true
+  sources = [
+    "simple_wm.cc",
+    "simple_wm.h",
+  ]
+
+  deps = [
+    "//base",
+    "//services/service_manager/public/cpp",
+    "//services/ui/public/cpp",
+    "//services/ui/public/interfaces",
+    "//ui/aura",
+    "//ui/aura:test_support",
+    "//ui/display",
+    "//ui/display:test_support",
+    "//ui/gfx/geometry/mojo",
+    "//ui/views",
+    "//ui/views/mus:mus",
+    "//ui/wm",
+  ]
+
+  public_deps = [
+    "//skia",  # Due to use of Sk types in service header.
+  ]
+
+  data_deps = [
+    ":manifest",
+    "//services/ui",
+  ]
+}
+
+service_manifest("manifest") {
+  name = "simple_wm"
+  source = "manifest.json"
+}