Wires up immersive mode for chrome and mash

ash/mus/frame/detached_title_area_renderer_host.h

Index: ash/mus/frame/detached_title_area_renderer_host.h
diff --git a/ash/mus/frame/detached_title_area_renderer_host.h b/ash/mus/frame/detached_title_area_renderer_host.h
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index 0000000000000000000000000000000000000000..416c028e61a9905a98e6b5a048d03547f9960e49
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+++ b/ash/mus/frame/detached_title_area_renderer_host.h
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+// 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.
+
+#ifndef ASH_MUS_FRAME_DETATCHED_TITLE_AREA_RENDERER_HOST_H_
+#define ASH_MUS_FRAME_DETATCHED_TITLE_AREA_RENDERER_HOST_H_
+
+namespace ash {
+namespace mus {
+
+class DetachedTitleAreaRenderer;
+
+// Used to inform the creator of DetachedTitleAreaRenderer of interesting
+// events.
+class DetachedTitleAreaRendererHost {
+ public:
+  virtual void OnDetachedTitleAreaRendererDestroyed(
+      DetachedTitleAreaRenderer* renderer) = 0;
+
+ protected:
+  virtual ~DetachedTitleAreaRendererHost() {}
+};
+
+}  // namespace mus
+}  // namespace ash
+
+#endif  // ASH_MUS_FRAME_DETATCHED_TITLE_AREA_RENDERER_HOST_H_