A11y setting: mono audio UI

chromeos/audio/audio_a11y_controller.h

Index: chromeos/audio/audio_a11y_controller.h
diff --git a/chromeos/audio/audio_a11y_controller.h b/chromeos/audio/audio_a11y_controller.h
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index 0000000000000000000000000000000000000000..8454131b7c80eaa6c0265f17ded929c433c934fc
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+++ b/chromeos/audio/audio_a11y_controller.h
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+// Copyright (c) 2013 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 CHROMEOS_AUDIO_AUDIO_A11Y_CONTROLLER_H_
+#define CHROMEOS_AUDIO_AUDIO_A11Y_CONTROLLER_H_
+
+#include <stdint.h>
+
+#include "base/macros.h"
+#include "chromeos/chromeos_export.h"
+
+namespace chromeos {
+
+class CHROMEOS_EXPORT AudioA11yController {
+ public:
+  AudioA11yController();
+  ~AudioA11yController();
+
+  // Set audio outputs mono or not (that is stereo).
+  void SetOutputMono(bool enabled);
+
+  // Returns true if audio output is mono, otherwise false.
+  bool IsOutputMonoEnabled() const;
+
+ private:
+  // Audio output channel counts.
+  int32_t channels_ = 2;
+
+  // Indicates if the mono audio output is enabled or disabled.
+  bool output_mono_enabled_ = false;
+
+  DISALLOW_COPY_AND_ASSIGN(AudioA11yController);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROMEOS_AUDIO_AUDIO_A11Y_CONTROLLER_H_