Stop chromevox audio and clear focus highlight on switch to arc app

ash/common/default_accessibility_delegate.cc

 // Copyright 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.
 
 #include "ash/common/default_accessibility_delegate.h"
 
 #include <limits>
 
 namespace ash {
 
@@ skipping 106 matching lines @@
          screen_magnifier_enabled_ || large_cursor_enabled_ ||
          autoclick_enabled_ || virtual_keyboard_enabled_ || mono_audio_enabled_;
 }
 
 bool DefaultAccessibilityDelegate::IsBrailleDisplayConnected() const {
   return false;
 }
 
 void DefaultAccessibilityDelegate::SilenceSpokenFeedback() const {}
 
+void DefaultAccessibilityDelegate::ClearFocusHighlight() const {}
+
 void DefaultAccessibilityDelegate::ToggleSpokenFeedback(
     AccessibilityNotificationVisibility notify) {
   spoken_feedback_enabled_ = !spoken_feedback_enabled_;
 }
 
 void DefaultAccessibilityDelegate::SaveScreenMagnifierScale(double scale) {}
 
 double DefaultAccessibilityDelegate::GetSavedScreenMagnifierScale() {
   return std::numeric_limits<double>::min();
 }
@@ skipping 10 matching lines @@
 void DefaultAccessibilityDelegate::PlayEarcon(int sound_key) {}
 
 base::TimeDelta DefaultAccessibilityDelegate::PlayShutdownSound() const {
   return base::TimeDelta();
 }
 
 void DefaultAccessibilityDelegate::HandleAccessibilityGesture(
     ui::AXGesture gesture) {}
 
 }  // namespace ash