[Athena] minimum impl to add screen/background and test windows

athena/wm/public/window_manager.h

Index: athena/wm/public/window_manager.h
diff --git a/athena/wm/public/window_manager.h b/athena/wm/public/window_manager.h
new file mode 100644
index 0000000000000000000000000000000000000000..6aa9ffcb5a63ccce14d059383ba33213e1726d1b
--- /dev/null
+++ b/athena/wm/public/window_manager.h
@@ -0,0 +1,22 @@
+// 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.
+
+#ifndef ATHENA_SCREEN_PUBLIC_WINDOW_MANAGER_H_
+#define ATHENA_SCREEN_PUBLIC_WINDOW_MANAGER_H_
+
+#include "athena/athena_export.h"
+
+namespace athena {
+
+class ATHENA_EXPORT WindowManager {
+ public:
+  static WindowManager* Create();
+  static void Shutdown();
+
+  virtual ~WindowManager() {}
+};
+
+}  // namespace athena
+
+#endif  // ATHENA_SCREEN_PUBLIC_WINDOW_MANAGER_H_