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

ash/display/display_manager.cc

 // Copyright (c) 2012 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/display/display_manager.h"
 
 #include <algorithm>
 #include <cmath>
 #include <set>
 #include <string>
@@ skipping 21 matching lines @@
 #include "ui/gfx/screen.h"
 #include "ui/gfx/size_conversions.h"
 
 #if defined(USE_X11)
 #include "ui/base/x/x11_util.h"
 #endif
 
 #if defined(OS_CHROMEOS)
 #include "ash/display/display_configurator_animation.h"
 #include "base/sys_info.h"
+#include "chromeos/audio/cras_audio_handler.h"
 #endif
 
 #if defined(OS_WIN)
 #include "base/win/windows_version.h"
 #endif
 
 namespace ash {
 typedef std::vector<gfx::Display> DisplayList;
 typedef std::vector<DisplayInfo> DisplayInfoList;
 
@@ skipping 378 matching lines @@
     DisplayInfo info = GetDisplayInfo(iter->id());
     if (info.id() == display_id) {
       if (info.rotation() == rotation)
         return;
       info.set_rotation(rotation);
     }
     display_info_list.push_back(info);
   }
   AddMirrorDisplayInfoIfAny(&display_info_list);
   UpdateDisplays(display_info_list);
+
+#if defined(OS_CHROMEOS)
+  // Swap the left/right channel of the speaker only if it is yoga mode.

[oshima, 2014/09/30 22:29:53]

1) Can you use gfx::DisplayObserver::OnDisplayMetricsChanged?

2) You need to check if the display is for internal display as you can rotate
external display.

3) You can rotate display on any display, so this happens when a user rotate
screen 180 on any chromebook. Is this ok?

[jennyz, 2014/10/01 00:22:59]

Thanks for pointing me to gfx::DisplayObserver::OnDisplayMetricsChanged, this
makes the code much easier and clean.
I think it is ok to swap the audio channel when the display is rotated, which is
a rare case for user anyway.

+  chromeos::CrasAudioHandler::Get()->SwapLeftRight(rotation ==
+                                                   gfx::Display::ROTATE_180);
+#endif
 }
 
 void DisplayManager::SetDisplayUIScale(int64 display_id,
                                        float ui_scale) {
   if (!IsDisplayUIScalingEnabled() ||
       gfx::Display::InternalDisplayId() != display_id) {
     return;
   }
 
   // TODO(mukai): merge this implementation into SetDisplayMode().
@@ skipping 809 matching lines @@
       new_secondary_origin.Offset(-secondary_bounds.width(), offset);
       break;
   }
   gfx::Insets insets = secondary_display->GetWorkAreaInsets();
   secondary_display->set_bounds(
       gfx::Rect(new_secondary_origin, secondary_bounds.size()));
   secondary_display->UpdateWorkAreaFromInsets(insets);
 }
 
 }  // namespace ash