Flip the left/right speaker when the device is in yoga mode.

ash/system/audio/tray_audio.cc

 // Copyright 2014 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/system/audio/tray_audio.h"
 
 #include <cmath>
 
 #include "ash/ash_constants.h"
+#include "ash/display/display_manager.h"
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/shell.h"
 #include "ash/system/audio/tray_audio_delegate.h"
 #include "ash/system/audio/volume_view.h"
 #include "ash/system/tray/actionable_view.h"
 #include "ash/system/tray/fixed_sized_scroll_view.h"
 #include "ash/system/tray/hover_highlight_view.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "ash/system/tray/system_tray_notifier.h"
 #include "ash/system/tray/tray_constants.h"
 #include "ash/volume_control_delegate.h"
 #include "base/strings/utf_string_conversions.h"
 #include "grit/ash_resources.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkPaint.h"
 #include "third_party/skia/include/core/SkRect.h"
 #include "third_party/skia/include/effects/SkGradientShader.h"
 #include "ui/gfx/canvas.h"
+#include "ui/gfx/display.h"
 #include "ui/gfx/font_list.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/image/image_skia_operations.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/controls/slider.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/view.h"
 
@@ skipping 81 matching lines @@
     PopupDetailedView(kTrayPopupAutoCloseDelayInSeconds, false);
   }
 }
 
 void TrayAudio::OnAudioNodesChanged() {
   Update();
 }
 
 void TrayAudio::OnActiveOutputNodeChanged() {
   Update();
+  // Swap left/right channel if it is in Yoga mode.
+  const DisplayInfo& display_info =
+      Shell::GetInstance()->display_manager()->GetDisplayInfo(
+          gfx::Display::InternalDisplayId());
+  audio_delegate_->SwapLeftRight(display_info.rotation() ==
+                                 gfx::Display::ROTATE_180);
 }
 
 void TrayAudio::OnActiveInputNodeChanged() {
   Update();
 }
 
 void TrayAudio::Update() {
   if (tray_view())
       tray_view()->SetVisible(GetInitialVisibility());
   if (volume_view_) {
     volume_view_->SetVolumeLevel(
         static_cast<float>(audio_delegate_->GetOutputVolumeLevel()) / 100.0f);
     volume_view_->Update();
   }
 }
 
 }  // namespace ash