mustash: Enable connections to mus from the Chrome renderer [take 2]

content/browser/mus_util.cc

Index: content/browser/mus_util.cc
diff --git a/content/browser/mus_util.cc b/content/browser/mus_util.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f600b732f5eebca81c4cfe1af325fb83fa945efc
--- /dev/null
+++ b/content/browser/mus_util.cc
@@ -0,0 +1,17 @@
+// 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.
+
+#include "content/browser/mus_util.h"
+
+#include "ui/aura/window.h"
+
+namespace content {
+
+mus::Window* GetMusWindow(aura::Window* window) {
+  if (!window)
+    return nullptr;
+  return static_cast<mus::Window*>(window->GetNativeWindowProperty("mus"));
+}
+
+}  // namespace content