A11y setting: mono audio UI

ash/accessibility_delegate.h

Index: ash/accessibility_delegate.h
diff --git a/ash/accessibility_delegate.h b/ash/accessibility_delegate.h
index f702c2a2e2ea5dc729d84a0f253a8f7a77958aab..b677cf9ecf424737a3bb3786de9b24ba6271f8be 100644
--- a/ash/accessibility_delegate.h
+++ b/ash/accessibility_delegate.h
@@ -59,6 +59,12 @@ class ASH_EXPORT AccessibilityDelegate {
   // Returns if the a11y virtual keyboard is enabled.
   virtual bool IsVirtualKeyboardEnabled() const = 0;
 
+  // Invoked to enable or disable the mono audio output.
+  virtual void SetMonoAudioEnabled(bool enabled) = 0;
+
+  // Returns if the mono audio output is enabled.
+  virtual bool IsMonoAudioEnabled() const = 0;
+
   // Invoked to enable or disable caret highlighting.
   virtual void SetCaretHighlightEnabled(bool enabled) = 0;