Revert 251959 "Refactor the TrayAudio code so that it can be use..."

Reverted due to memory leaks:
http://build.chromium.org/p/chromium.memory/builders/Linux%20Chromium%20OS%20ASAN%20Tests%20%281%29/builds/15922

> Refactor the TrayAudio code so that it can be used by other platforms.
> The motivation here is to introduce the volume slider tray UI into
> Windows Ash.
> 
> This change does not actually add tray audio UI to other platforms,
> only moves some non-chromeos specific things out of the chromeos
> platform folders, so that we can hook in the native Audio APIs
> of other platforms to the tray UI.
> 
> At a high level, this change does the following:
> 
> 1) Move tray_audio out of chromeos/ so that other platforms can
> use the UI that it provides.
> 2) Decouples TrayAudio from CrasAudioHandler by introducing a
> new delegate, in a similar vein to what is done with all the other
> handlers (e.g. the BluetoothHandler)
> 3) Move the additional views (VolumeView, etc) to their own files
> so they can be used by other platforms as well.
> 
> TEST=
>  On CrOS physical device, verified that:
>  1) Keyboard volume buttons function appropriately and display the
>     volume view
>  2) AudioDetailView still is accessible at the correct times
>  3) Adjusting the volume (via the keyboard shortcuts or via the
>     slider) correctly change the output volume.
>  4) UI still behaves correctly (e.g. icons update as the volume
>     changes, mute button works, etc).
> 
> BUG=227247
> 
> Review URL: https://codereview.chromium.org/163953007

TBR=zturner@chromium.org

Review URL: https://codereview.chromium.org/170843009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252009 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 724 insertions, 440 deletions

diff --git a/ash/system/chromeos/audio/audio_detailed_view.cc b/ash/system/chromeos/audio/audio_detailed_view.cc
deleted file mode 100644
index 803f4dd..0000000
--- a/ash/system/chromeos/audio/audio_detailed_view.cc
+++ /dev/null
@@ -1,177 +0,0 @@
-// 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/chromeos/audio/audio_detailed_view.h"
-
-#include "ash/system/tray/fixed_sized_scroll_view.h"
-#include "ash/system/tray/hover_highlight_view.h"
-#include "ash/system/tray/tray_constants.h"
-#include "base/strings/utf_string_conversions.h"
-#include "chromeos/audio/cras_audio_handler.h"
-#include "grit/ash_resources.h"
-#include "grit/ash_strings.h"
-#include "ui/base/l10n/l10n_util.h"
-#include "ui/base/resource/resource_bundle.h"
-#include "ui/views/border.h"
-#include "ui/views/controls/label.h"
-
-namespace {
-
-base::string16 GetAudioDeviceName(const chromeos::AudioDevice& device) {
-  switch(device.type) {
-    case chromeos::AUDIO_TYPE_HEADPHONE:
-      return l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_HEADPHONE);
-    case chromeos::AUDIO_TYPE_INTERNAL_SPEAKER:
-      return l10n_util::GetStringUTF16(
-          IDS_ASH_STATUS_TRAY_AUDIO_INTERNAL_SPEAKER);
-    case chromeos::AUDIO_TYPE_INTERNAL_MIC:
-      return l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_INTERNAL_MIC);
-    case chromeos::AUDIO_TYPE_USB:
-      return l10n_util::GetStringFUTF16(
-          IDS_ASH_STATUS_TRAY_AUDIO_USB_DEVICE,
-          base::UTF8ToUTF16(device.display_name));
-    case chromeos::AUDIO_TYPE_BLUETOOTH:
-      return l10n_util::GetStringFUTF16(
-          IDS_ASH_STATUS_TRAY_AUDIO_BLUETOOTH_DEVICE,
-          base::UTF8ToUTF16(device.display_name));
-    case chromeos::AUDIO_TYPE_HDMI:
-      return l10n_util::GetStringFUTF16(
-          IDS_ASH_STATUS_TRAY_AUDIO_HDMI_DEVICE,
-          base::UTF8ToUTF16(device.display_name));
-    default:
-      return base::UTF8ToUTF16(device.display_name);
-  }
-}
-
-}  // namespace
-
-using chromeos::CrasAudioHandler;
-
-namespace ash {
-namespace internal {
-namespace tray {
-
-AudioDetailedView::AudioDetailedView(SystemTrayItem* owner,
-                                     user::LoginStatus login)
-    : TrayDetailsView(owner),
-      login_(login) {
-  CreateItems();
-  Update();
-}
-
-AudioDetailedView::~AudioDetailedView() {
-}
-
-void AudioDetailedView::Update() {
-  UpdateAudioDevices();
-  Layout();
-}
-
-void AudioDetailedView::AddScrollListInfoItem(const base::string16& text) {
-  views::Label* label = new views::Label(
-      text,
-      ui::ResourceBundle::GetSharedInstance().GetFontList(
-          ui::ResourceBundle::BoldFont));
-
-  //  Align info item with checkbox items
-  int margin = kTrayPopupPaddingHorizontal +
-      kTrayPopupDetailsLabelExtraLeftMargin;
-  int left_margin = 0;
-  int right_margin = 0;
-  if (base::i18n::IsRTL())
-    right_margin = margin;
-  else
-    left_margin = margin;
-
-  label->SetBorder(views::Border::CreateEmptyBorder(
-      ash::kTrayPopupPaddingBetweenItems,
-      left_margin,
-      ash::kTrayPopupPaddingBetweenItems,
-      right_margin));
-  label->SetHorizontalAlignment(gfx::ALIGN_LEFT);
-  label->SetEnabledColor(SkColorSetARGB(192, 0, 0, 0));
-
-  scroll_content()->AddChildView(label);
-}
-
-HoverHighlightView* AudioDetailedView::AddScrollListItem(
-    const base::string16& text,
-    gfx::Font::FontStyle style,
-    bool checked) {
-  HoverHighlightView* container = new HoverHighlightView(this);
-  container->AddCheckableLabel(text, style, checked);
-  scroll_content()->AddChildView(container);
-  return container;
-}
-
-void AudioDetailedView::CreateHeaderEntry() {
-  CreateSpecialRow(IDS_ASH_STATUS_TRAY_AUDIO, this);
-}
-
-void AudioDetailedView::CreateItems() {
-  CreateScrollableList();
-  CreateHeaderEntry();
-}
-
-void AudioDetailedView::UpdateAudioDevices() {
-  output_devices_.clear();
-  input_devices_.clear();
-  chromeos::AudioDeviceList devices;
-  CrasAudioHandler::Get()->GetAudioDevices(&devices);
-  for (size_t i = 0; i < devices.size(); ++i) {
-    if (devices[i].is_input)
-      input_devices_.push_back(devices[i]);
-    else
-      output_devices_.push_back(devices[i]);
-  }
-  UpdateScrollableList();
-}
-
-void AudioDetailedView::UpdateScrollableList() {
-  scroll_content()->RemoveAllChildViews(true);
-  device_map_.clear();
-
-  // Add audio output devices.
-  AddScrollListInfoItem(
-      l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_OUTPUT));
-  for (size_t i = 0; i < output_devices_.size(); ++i) {
-    HoverHighlightView* container = AddScrollListItem(
-        GetAudioDeviceName(output_devices_[i]),
-        gfx::Font::NORMAL,
-        output_devices_[i].active);  /* checkmark if active */
-    device_map_[container] = output_devices_[i];
-  }
-
-  AddScrollSeparator();
-
-  // Add audio input devices.
-  AddScrollListInfoItem(
-      l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_INPUT));
-  for (size_t i = 0; i < input_devices_.size(); ++i) {
-    HoverHighlightView* container = AddScrollListItem(
-        GetAudioDeviceName(input_devices_[i]),
-        gfx::Font::NORMAL,
-        input_devices_[i].active);  /* checkmark if active */
-    device_map_[container] = input_devices_[i];
-  }
-
-  scroll_content()->SizeToPreferredSize();
-  scroller()->Layout();
-}
-
-void AudioDetailedView::OnViewClicked(views::View* sender) {
-  if (sender == footer()->content()) {
-    TransitionToDefaultView();
-  } else {
-    AudioDeviceMap::iterator iter = device_map_.find(sender);
-    if (iter == device_map_.end())
-      return;
-    chromeos::AudioDevice& device = iter->second;
-    CrasAudioHandler::Get()->SwitchToDevice(device);
-  }
-}
-
-}  // namespace tray
-}  // namespace internal
-}  // namespace ash
diff --git a/ash/system/chromeos/audio/audio_detailed_view.h b/ash/system/chromeos/audio/audio_detailed_view.h
deleted file mode 100644
index 6953676..0000000
--- a/ash/system/chromeos/audio/audio_detailed_view.h
+++ /dev/null
@@ -1,66 +0,0 @@
-// 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.
-
-#ifndef ASH_SYSTEM_CHROMEOS_AUDIO_AUDIO_DETAILED_VIEW_H_
-#define ASH_SYSTEM_CHROMEOS_AUDIO_AUDIO_DETAILED_VIEW_H_
-
-#include "ash/system/tray/tray_details_view.h"
-#include "ash/system/tray/view_click_listener.h"
-#include "ash/system/user/login_status.h"
-#include "chromeos/audio/audio_device.h"
-
-#include "ui/gfx/font.h"
-
-namespace views {
-class View;
-}
-
-namespace ash {
-namespace internal {
-
-class HoverHighlightView;
-
-namespace tray {
-
-class AudioDetailedView : public TrayDetailsView,
-                          public ViewClickListener {
- public:
-  AudioDetailedView(SystemTrayItem* owner, user::LoginStatus login);
-
-  virtual ~AudioDetailedView();
-
-  void Update();
-
- private:
-  void AddScrollListInfoItem(const base::string16& text);
-
-  HoverHighlightView* AddScrollListItem(const base::string16& text,
-                                        gfx::Font::FontStyle style,
-                                        bool checked);
-
-  void CreateHeaderEntry();
-  void CreateItems();
-
-  void UpdateScrollableList();
-  void UpdateAudioDevices();
-
-  // Overridden from ViewClickListener.
-  virtual void OnViewClicked(views::View* sender) OVERRIDE;
-
-  user::LoginStatus login_;
-
-  typedef std::map<views::View*, chromeos::AudioDevice> AudioDeviceMap;
-
-  chromeos::AudioDeviceList output_devices_;
-  chromeos::AudioDeviceList input_devices_;
-  AudioDeviceMap device_map_;
-
-  DISALLOW_COPY_AND_ASSIGN(AudioDetailedView);
-};
-
-}  // namespace tray
-}  // namespace internal
-}  // namespace ash
-
-#endif  // ASH_SYSTEM_CHROMEOS_AUDIO_AUDIO_DETAILED_VIEW_H_
diff --git a/ash/system/chromeos/audio/tray_audio.cc b/ash/system/chromeos/audio/tray_audio.cc
new file mode 100644
index 0000000..c1721f6
--- /dev/null
+++ b/ash/system/chromeos/audio/tray_audio.cc
@@ -0,0 +1,663 @@
+// 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/system/chromeos/audio/tray_audio.h"
+
+#include <cmath>
+
+#include "ash/ash_constants.h"
+#include "ash/ash_switches.h"
+#include "ash/metrics/user_metrics_recorder.h"
+#include "ash/shell.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 "chromeos/audio/cras_audio_handler.h"
+#include "grit/ash_resources.h"
+#include "grit/ash_strings.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/base/l10n/l10n_util.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/gfx/canvas.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"
+
+using chromeos::CrasAudioHandler;
+
+namespace ash {
+namespace internal {
+
+namespace {
+const int kVolumeImageWidth = 25;
+const int kVolumeImageHeight = 25;
+const int kBarSeparatorWidth = 25;
+const int kBarSeparatorHeight = 30;
+const int kSliderRightPaddingToVolumeViewEdge = 17;
+const int kExtraPaddingBetweenBarAndMore = 10;
+
+const int kNoAudioDeviceIcon = -1;
+
+// IDR_AURA_UBER_TRAY_VOLUME_LEVELS contains 5 images,
+// The one for mute is at the 0 index and the other
+// four are used for ascending volume levels.
+const int kVolumeLevels = 4;
+
+bool IsAudioMuted() {
+  return CrasAudioHandler::Get()->IsOutputMuted();
+}
+
+float GetVolumeLevel() {
+  return CrasAudioHandler::Get()->GetOutputVolumePercent() / 100.0f;
+}
+
+int GetAudioDeviceIconId(chromeos::AudioDeviceType type) {
+  if (type == chromeos::AUDIO_TYPE_HEADPHONE)
+    return IDR_AURA_UBER_TRAY_AUDIO_HEADPHONE;
+  else if (type == chromeos::AUDIO_TYPE_USB)
+    return IDR_AURA_UBER_TRAY_AUDIO_USB;
+  else if (type == chromeos::AUDIO_TYPE_BLUETOOTH)
+    return IDR_AURA_UBER_TRAY_AUDIO_BLUETOOTH;
+  else if (type == chromeos::AUDIO_TYPE_HDMI)
+    return IDR_AURA_UBER_TRAY_AUDIO_HDMI;
+  else
+    return kNoAudioDeviceIcon;
+}
+
+base::string16 GetAudioDeviceName(const chromeos::AudioDevice& device) {
+  switch(device.type) {
+    case chromeos::AUDIO_TYPE_HEADPHONE:
+      return l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_HEADPHONE);
+    case chromeos::AUDIO_TYPE_INTERNAL_SPEAKER:
+      return l10n_util::GetStringUTF16(
+          IDS_ASH_STATUS_TRAY_AUDIO_INTERNAL_SPEAKER);
+    case chromeos::AUDIO_TYPE_INTERNAL_MIC:
+      return l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_INTERNAL_MIC);
+    case chromeos::AUDIO_TYPE_USB:
+      return l10n_util::GetStringFUTF16(
+          IDS_ASH_STATUS_TRAY_AUDIO_USB_DEVICE,
+          base::UTF8ToUTF16(device.display_name));
+    case chromeos::AUDIO_TYPE_BLUETOOTH:
+      return l10n_util::GetStringFUTF16(
+          IDS_ASH_STATUS_TRAY_AUDIO_BLUETOOTH_DEVICE,
+          base::UTF8ToUTF16(device.display_name));
+    case chromeos::AUDIO_TYPE_HDMI:
+      return l10n_util::GetStringFUTF16(
+          IDS_ASH_STATUS_TRAY_AUDIO_HDMI_DEVICE,
+          base::UTF8ToUTF16(device.display_name));
+    default:
+      return base::UTF8ToUTF16(device.display_name);
+  }
+}
+
+}  // namespace
+
+namespace tray {
+
+class VolumeButton : public views::ToggleImageButton {
+ public:
+  explicit VolumeButton(views::ButtonListener* listener)
+      : views::ToggleImageButton(listener),
+        image_index_(-1) {
+    SetImageAlignment(ALIGN_CENTER, ALIGN_MIDDLE);
+    image_ = ui::ResourceBundle::GetSharedInstance().GetImageNamed(
+        IDR_AURA_UBER_TRAY_VOLUME_LEVELS);
+    SetPreferredSize(gfx::Size(kTrayPopupItemHeight, kTrayPopupItemHeight));
+    Update();
+  }
+
+  virtual ~VolumeButton() {}
+
+  void Update() {
+    float level = GetVolumeLevel();
+    int image_index = IsAudioMuted() ?
+        0 : (level == 1.0 ?
+             kVolumeLevels :
+             std::max(1, int(std::ceil(level * (kVolumeLevels - 1)))));
+    if (image_index != image_index_) {
+      gfx::Rect region(0, image_index * kVolumeImageHeight,
+                       kVolumeImageWidth, kVolumeImageHeight);
+      gfx::ImageSkia image_skia = gfx::ImageSkiaOperations::ExtractSubset(
+          *(image_.ToImageSkia()), region);
+      SetImage(views::CustomButton::STATE_NORMAL, &image_skia);
+      image_index_ = image_index;
+    }
+    SchedulePaint();
+  }
+
+ private:
+  // Overridden from views::View.
+  virtual gfx::Size GetPreferredSize() OVERRIDE {
+    gfx::Size size = views::ToggleImageButton::GetPreferredSize();
+    size.set_height(kTrayPopupItemHeight);
+    return size;
+  }
+
+  gfx::Image image_;
+  int image_index_;
+
+  DISALLOW_COPY_AND_ASSIGN(VolumeButton);
+};
+
+class VolumeSlider : public views::Slider {
+ public:
+  explicit VolumeSlider(views::SliderListener* listener)
+      : views::Slider(listener, views::Slider::HORIZONTAL) {
+    set_focus_border_color(kFocusBorderColor);
+    SetValue(GetVolumeLevel());
+    SetAccessibleName(
+            ui::ResourceBundle::GetSharedInstance().GetLocalizedString(
+                IDS_ASH_STATUS_TRAY_VOLUME));
+    Update();
+  }
+  virtual ~VolumeSlider() {}
+
+  void Update() {
+    UpdateState(!IsAudioMuted());
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(VolumeSlider);
+};
+
+// Vertical bar separator that can be placed on the VolumeView.
+class BarSeparator : public views::View {
+ public:
+  BarSeparator() {}
+  virtual ~BarSeparator() {}
+
+  // Overriden from views::View.
+  virtual gfx::Size GetPreferredSize() OVERRIDE {
+    return gfx::Size(kBarSeparatorWidth, kBarSeparatorHeight);
+  }
+
+ private:
+  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE {
+    canvas->FillRect(gfx::Rect(width() / 2, 0, 1, height()),
+                     kButtonStrokeColor);
+  }
+
+  DISALLOW_COPY_AND_ASSIGN(BarSeparator);
+};
+
+class VolumeView : public ActionableView,
+                   public views::ButtonListener,
+                   public views::SliderListener {
+ public:
+  VolumeView(SystemTrayItem* owner, bool is_default_view)
+      : owner_(owner),
+        icon_(NULL),
+        slider_(NULL),
+        bar_(NULL),
+        device_type_(NULL),
+        more_(NULL),
+        is_default_view_(is_default_view) {
+    SetFocusable(false);
+    SetLayoutManager(new views::BoxLayout(views::BoxLayout::kHorizontal,
+          kTrayPopupPaddingHorizontal, 0, kTrayPopupPaddingBetweenItems));
+
+    icon_ = new VolumeButton(this);
+    AddChildView(icon_);
+
+    slider_ = new VolumeSlider(this);
+    AddChildView(slider_);
+
+    bar_ = new BarSeparator;
+    AddChildView(bar_);
+
+    device_type_ = new views::ImageView;
+    AddChildView(device_type_);
+
+    more_ = new views::ImageView;
+    more_->EnableCanvasFlippingForRTLUI(true);
+    more_->SetImage(ui::ResourceBundle::GetSharedInstance().GetImageNamed(
+        IDR_AURA_UBER_TRAY_MORE).ToImageSkia());
+    AddChildView(more_);
+
+    Update();
+  }
+
+  virtual ~VolumeView() {}
+
+  void Update() {
+    icon_->Update();
+    slider_->Update();
+    UpdateDeviceTypeAndMore();
+    Layout();
+  }
+
+  // Sets volume level on slider_, |percent| is ranged from [0.00] to [1.00].
+  void SetVolumeLevel(float percent) {
+    // Slider's value is in finer granularity than audio volume level(0.01),
+    // there will be a small discrepancy between slider's value and volume level
+    // on audio side. To avoid the jittering in slider UI, do not set change
+    // slider value if the change is less than 1%.
+    if (std::abs(percent-slider_->value()) < 0.01)
+      return;
+    // The change in volume will be reflected via accessibility system events,
+    // so we prevent the UI event from being sent here.
+    slider_->set_enable_accessibility_events(false);
+    slider_->SetValue(percent);
+    // It is possible that the volume was (un)muted, but the actual volume level
+    // did not change. In that case, setting the value of the slider won't
+    // trigger an update. So explicitly trigger an update.
+    Update();
+    slider_->set_enable_accessibility_events(true);
+  }
+
+ private:
+  // Updates bar_, device_type_ icon, and more_ buttons.
+  void UpdateDeviceTypeAndMore() {
+    if (!ash::switches::ShowAudioDeviceMenu() || !is_default_view_) {
+      more_->SetVisible(false);
+      bar_->SetVisible(false);
+      device_type_->SetVisible(false);
+      return;
+    }
+
+    CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
+    bool show_more = audio_handler->has_alternative_output() ||
+                     audio_handler->has_alternative_input();
+    more_->SetVisible(show_more);
+
+    // Show output device icon if necessary.
+    chromeos::AudioDevice device;
+    if (!audio_handler->GetActiveOutputDevice(&device))
+      return;
+    int device_icon = GetAudioDeviceIconId(device.type);
+    bar_->SetVisible(show_more);
+    if (device_icon != kNoAudioDeviceIcon) {
+      device_type_->SetVisible(true);
+      device_type_->SetImage(
+          ui::ResourceBundle::GetSharedInstance().GetImageNamed(
+              device_icon).ToImageSkia());
+    } else {
+      device_type_->SetVisible(false);
+    }
+  }
+
+  void HandleVolumeUp(int volume) {
+    CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
+    audio_handler->SetOutputVolumePercent(volume);
+    if (audio_handler->IsOutputMuted() &&
+        !audio_handler->IsOutputVolumeBelowDefaultMuteLvel())
+      audio_handler->SetOutputMute(false);
+  }
+
+  void HandleVolumeDown(int volume) {
+    CrasAudioHandler* audio_handler =  CrasAudioHandler::Get();
+    audio_handler->SetOutputVolumePercent(volume);
+    if (audio_handler->IsOutputVolumeBelowDefaultMuteLvel() &&
+        !audio_handler->IsOutputMuted()) {
+      audio_handler->SetOutputMute(true);
+    } else if (!audio_handler->IsOutputVolumeBelowDefaultMuteLvel() &&
+               audio_handler->IsOutputMuted()) {
+      audio_handler->SetOutputMute(false);
+    }
+  }
+
+  // Overridden from views::View.
+  virtual void Layout() OVERRIDE {
+    views::View::Layout();
+
+    if (!more_->visible()) {
+      int w = width() - slider_->bounds().x() -
+              kSliderRightPaddingToVolumeViewEdge;
+      slider_->SetSize(gfx::Size(w, slider_->height()));
+      return;
+    }
+
+    // Make sure the chevron always has the full size.
+    gfx::Size size = more_->GetPreferredSize();
+    gfx::Rect bounds(size);
+    bounds.set_x(width() - size.width() - kTrayPopupPaddingBetweenItems);
+    bounds.set_y((height() - size.height()) / 2);
+    more_->SetBoundsRect(bounds);
+
+    // Layout either bar_ or device_type_ at the left of the more_ button.
+    views::View* view_left_to_more;
+    if (device_type_->visible())
+      view_left_to_more = device_type_;
+    else
+      view_left_to_more = bar_;
+    gfx::Size view_size = view_left_to_more->GetPreferredSize();
+    gfx::Rect view_bounds(view_size);
+    view_bounds.set_x(more_->bounds().x() - view_size.width() -
+                     kExtraPaddingBetweenBarAndMore);
+    view_bounds.set_y((height() - view_size.height()) / 2);
+    view_left_to_more->SetBoundsRect(view_bounds);
+
+    // Layout vertical bar next to view_left_to_more if device_type_ is visible.
+    if (device_type_->visible()) {
+      gfx::Size bar_size = bar_->GetPreferredSize();
+      gfx::Rect bar_bounds(bar_size);
+      bar_bounds.set_x(view_left_to_more->bounds().x() - bar_size.width());
+      bar_bounds.set_y((height() - bar_size.height()) / 2);
+      bar_->SetBoundsRect(bar_bounds);
+    }
+
+    // Layout slider, calculate slider width.
+    gfx::Rect slider_bounds = slider_->bounds();
+    slider_bounds.set_width(
+        bar_->bounds().x()
+        - (device_type_->visible() ? 0 : kTrayPopupPaddingBetweenItems)
+        - slider_bounds.x());
+    slider_->SetBoundsRect(slider_bounds);
+  }
+
+  // Overridden from views::ButtonListener.
+  virtual void ButtonPressed(views::Button* sender,
+                             const ui::Event& event) OVERRIDE {
+    CHECK(sender == icon_);
+    bool mute_on = !IsAudioMuted();
+    CrasAudioHandler::Get()->SetOutputMute(mute_on);
+    if (!mute_on)
+      CrasAudioHandler::Get()->AdjustOutputVolumeToAudibleLevel();
+  }
+
+  // Overridden from views:SliderListener.
+  virtual void SliderValueChanged(views::Slider* sender,
+                                  float value,
+                                  float old_value,
+                                  views::SliderChangeReason reason) OVERRIDE {
+    if (reason == views::VALUE_CHANGED_BY_USER) {
+      int volume = value * 100.0f;
+      int old_volume = CrasAudioHandler::Get()->GetOutputVolumePercent();
+      // Do not call change audio volume if the difference is less than
+      // 1%, which is beyond cras audio api's granularity for output volume.
+      if (std::abs(volume - old_volume) < 1)
+        return;
+      Shell::GetInstance()->metrics()->RecordUserMetricsAction(
+          is_default_view_ ?
+          ash::UMA_STATUS_AREA_CHANGED_VOLUME_MENU :
+          ash::UMA_STATUS_AREA_CHANGED_VOLUME_POPUP);
+      if (volume > old_volume)
+        HandleVolumeUp(volume);
+      else
+        HandleVolumeDown(volume);
+    }
+    icon_->Update();
+  }
+
+  // Overriden from ActionableView.
+  virtual bool PerformAction(const ui::Event& event) OVERRIDE {
+    if (!more_->visible())
+      return false;
+    owner_->TransitionDetailedView();
+    return true;
+  }
+
+  SystemTrayItem* owner_;
+  VolumeButton* icon_;
+  VolumeSlider* slider_;
+  BarSeparator* bar_;
+  views::ImageView* device_type_;
+  views::ImageView* more_;
+  bool is_default_view_;
+
+  DISALLOW_COPY_AND_ASSIGN(VolumeView);
+};
+
+class AudioDetailedView : public TrayDetailsView,
+                          public ViewClickListener {
+ public:
+  AudioDetailedView(SystemTrayItem* owner, user::LoginStatus login)
+      : TrayDetailsView(owner),
+        login_(login) {
+    CreateItems();
+    Update();
+  }
+
+  virtual ~AudioDetailedView() {
+  }
+
+  void Update() {
+    UpdateAudioDevices();
+    Layout();
+  }
+
+ private:
+  void CreateItems() {
+    CreateScrollableList();
+    CreateHeaderEntry();
+  }
+
+  void CreateHeaderEntry() {
+    CreateSpecialRow(IDS_ASH_STATUS_TRAY_AUDIO, this);
+  }
+
+  void UpdateAudioDevices() {
+    output_devices_.clear();
+    input_devices_.clear();
+    chromeos::AudioDeviceList devices;
+    CrasAudioHandler::Get()->GetAudioDevices(&devices);
+    for (size_t i = 0; i < devices.size(); ++i) {
+      if (devices[i].is_input)
+        input_devices_.push_back(devices[i]);
+      else
+        output_devices_.push_back(devices[i]);
+    }
+    UpdateScrollableList();
+  }
+
+  void UpdateScrollableList() {
+    scroll_content()->RemoveAllChildViews(true);
+    device_map_.clear();
+
+    // Add audio output devices.
+    AddScrollListInfoItem(
+        l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_OUTPUT));
+    for (size_t i = 0; i < output_devices_.size(); ++i) {
+      HoverHighlightView* container = AddScrollListItem(
+          GetAudioDeviceName(output_devices_[i]),
+          gfx::Font::NORMAL,
+          output_devices_[i].active);  /* checkmark if active */
+      device_map_[container] = output_devices_[i];
+    }
+
+    AddScrollSeparator();
+
+    // Add audio input devices.
+    AddScrollListInfoItem(
+        l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_AUDIO_INPUT));
+    for (size_t i = 0; i < input_devices_.size(); ++i) {
+      HoverHighlightView* container = AddScrollListItem(
+          GetAudioDeviceName(input_devices_[i]),
+          gfx::Font::NORMAL,
+          input_devices_[i].active);  /* checkmark if active */
+      device_map_[container] = input_devices_[i];
+    }
+
+    scroll_content()->SizeToPreferredSize();
+    scroller()->Layout();
+  }
+
+  void AddScrollListInfoItem(const base::string16& text) {
+    views::Label* label = new views::Label(
+        text,
+        ui::ResourceBundle::GetSharedInstance().GetFontList(
+            ui::ResourceBundle::BoldFont));
+
+    //  Align info item with checkbox items
+    int margin = kTrayPopupPaddingHorizontal +
+        kTrayPopupDetailsLabelExtraLeftMargin;
+    int left_margin = 0;
+    int right_margin = 0;
+    if (base::i18n::IsRTL())
+      right_margin = margin;
+    else
+      left_margin = margin;
+
+    label->SetBorder(
+        views::Border::CreateEmptyBorder(ash::kTrayPopupPaddingBetweenItems,
+                                         left_margin,
+                                         ash::kTrayPopupPaddingBetweenItems,
+                                         right_margin));
+    label->SetHorizontalAlignment(gfx::ALIGN_LEFT);
+    label->SetEnabledColor(SkColorSetARGB(192, 0, 0, 0));
+
+    scroll_content()->AddChildView(label);
+  }
+
+  HoverHighlightView* AddScrollListItem(const base::string16& text,
+                                        gfx::Font::FontStyle style,
+                                        bool checked) {
+    HoverHighlightView* container = new HoverHighlightView(this);
+    container->AddCheckableLabel(text, style, checked);
+    scroll_content()->AddChildView(container);
+    return container;
+  }
+
+  // Overridden from ViewClickListener.
+  virtual void OnViewClicked(views::View* sender) OVERRIDE {
+    if (sender == footer()->content()) {
+      TransitionToDefaultView();
+    } else {
+      AudioDeviceMap::iterator iter = device_map_.find(sender);
+      if (iter == device_map_.end())
+        return;
+      chromeos::AudioDevice& device = iter->second;
+      CrasAudioHandler::Get()->SwitchToDevice(device);
+    }
+  }
+
+  typedef std::map<views::View*, chromeos::AudioDevice> AudioDeviceMap;
+
+  user::LoginStatus login_;
+  chromeos::AudioDeviceList output_devices_;
+  chromeos::AudioDeviceList input_devices_;
+  AudioDeviceMap device_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(AudioDetailedView);
+};
+
+}  // namespace tray
+
+TrayAudio::TrayAudio(SystemTray* system_tray)
+    : TrayImageItem(system_tray, IDR_AURA_UBER_TRAY_VOLUME_MUTE),
+      volume_view_(NULL),
+      audio_detail_(NULL),
+      pop_up_volume_view_(false) {
+  CrasAudioHandler::Get()->AddAudioObserver(this);
+}
+
+TrayAudio::~TrayAudio() {
+  if (CrasAudioHandler::IsInitialized())
+    CrasAudioHandler::Get()->RemoveAudioObserver(this);
+}
+
+bool TrayAudio::GetInitialVisibility() {
+  return IsAudioMuted();
+}
+
+views::View* TrayAudio::CreateDefaultView(user::LoginStatus status) {
+  volume_view_ = new tray::VolumeView(this, true);
+  return volume_view_;
+}
+
+views::View* TrayAudio::CreateDetailedView(user::LoginStatus status) {
+  if (!ash::switches::ShowAudioDeviceMenu() || pop_up_volume_view_) {
+    volume_view_ = new tray::VolumeView(this, false);
+    return volume_view_;
+  } else {
+    Shell::GetInstance()->metrics()->RecordUserMetricsAction(
+        ash::UMA_STATUS_AREA_DETAILED_AUDIO_VIEW);
+    audio_detail_ = new tray::AudioDetailedView(this, status);
+    return audio_detail_;
+  }
+}
+
+void TrayAudio::DestroyDefaultView() {
+  volume_view_ = NULL;
+}
+
+void TrayAudio::DestroyDetailedView() {
+  if (audio_detail_) {
+    audio_detail_ = NULL;
+  } else if (volume_view_) {
+    volume_view_ = NULL;
+    pop_up_volume_view_ = false;
+  }
+}
+
+bool TrayAudio::ShouldHideArrow() const {
+  return true;
+}
+
+bool TrayAudio::ShouldShowShelf() const {
+  return ash::switches::ShowAudioDeviceMenu() && !pop_up_volume_view_;
+}
+
+void TrayAudio::OnOutputVolumeChanged() {
+  float percent = GetVolumeLevel();
+  if (tray_view())
+    tray_view()->SetVisible(GetInitialVisibility());
+
+  if (volume_view_) {
+    volume_view_->SetVolumeLevel(percent);
+    SetDetailedViewCloseDelay(kTrayPopupAutoCloseDelayInSeconds);
+    return;
+  }
+  pop_up_volume_view_ = true;
+  PopupDetailedView(kTrayPopupAutoCloseDelayInSeconds, false);
+}
+
+void TrayAudio::OnOutputMuteChanged() {
+  if (tray_view())
+      tray_view()->SetVisible(GetInitialVisibility());
+
+  if (volume_view_) {
+    volume_view_->Update();
+    SetDetailedViewCloseDelay(kTrayPopupAutoCloseDelayInSeconds);
+  } else {
+    pop_up_volume_view_ = true;
+    PopupDetailedView(kTrayPopupAutoCloseDelayInSeconds, false);
+  }
+}
+
+void TrayAudio::OnInputGainChanged() {
+}
+
+void TrayAudio::OnInputMuteChanged() {
+}
+
+void TrayAudio::OnAudioNodesChanged() {
+  Update();
+}
+
+void TrayAudio::OnActiveOutputNodeChanged() {
+  Update();
+}
+
+void TrayAudio::OnActiveInputNodeChanged() {
+  Update();
+}
+
+void TrayAudio::Update() {
+  if (tray_view())
+      tray_view()->SetVisible(GetInitialVisibility());
+  if (audio_detail_)
+    audio_detail_->Update();
+  if (volume_view_) {
+    volume_view_->SetVolumeLevel(GetVolumeLevel());
+    volume_view_->Update();
+  }
+}
+
+}  // namespace internal
+}  // namespace ash
diff --git a/ash/system/chromeos/audio/tray_audio.h b/ash/system/chromeos/audio/tray_audio.h
new file mode 100644
index 0000000..eb6e117a
--- /dev/null
+++ b/ash/system/chromeos/audio/tray_audio.h
@@ -0,0 +1,61 @@
+// 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.
+
+#ifndef ASH_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_H_
+#define ASH_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_H_
+
+#include "ash/system/tray/tray_image_item.h"
+#include "chromeos/audio/cras_audio_handler.h"
+
+namespace ash {
+namespace internal {
+
+namespace tray {
+class VolumeView;
+class AudioDetailedView;
+}
+
+class TrayAudio : public TrayImageItem,
+                  public chromeos::CrasAudioHandler::AudioObserver {
+ public:
+  explicit TrayAudio(SystemTray* system_tray);
+  virtual ~TrayAudio();
+
+ private:
+  // Overridden from TrayImageItem.
+  virtual bool GetInitialVisibility() OVERRIDE;
+
+  // Overridden from SystemTrayItem.
+  virtual views::View* CreateDefaultView(user::LoginStatus status) OVERRIDE;
+  virtual views::View* CreateDetailedView(user::LoginStatus status) OVERRIDE;
+  virtual void DestroyDefaultView() OVERRIDE;
+  virtual void DestroyDetailedView() OVERRIDE;
+  virtual bool ShouldHideArrow() const OVERRIDE;
+  virtual bool ShouldShowShelf() const OVERRIDE;
+
+  // Overridden from chromeos::CrasAudioHandler::AudioObserver.
+  virtual void OnOutputVolumeChanged() OVERRIDE;
+  virtual void OnOutputMuteChanged() OVERRIDE;
+  virtual void OnInputGainChanged() OVERRIDE;
+  virtual void OnInputMuteChanged() OVERRIDE;
+  virtual void OnAudioNodesChanged() OVERRIDE;
+  virtual void OnActiveOutputNodeChanged() OVERRIDE;
+  virtual void OnActiveInputNodeChanged() OVERRIDE;
+
+  void Update();
+
+  tray::VolumeView* volume_view_;
+  tray::AudioDetailedView* audio_detail_;
+
+  // True if VolumeView should be created for accelerator pop up;
+  // Otherwise, it should be created for detailed view in ash tray bubble.
+  bool pop_up_volume_view_;
+
+  DISALLOW_COPY_AND_ASSIGN(TrayAudio);
+};
+
+}  // namespace internal
+}  // namespace ash
+
+#endif  // ASH_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_H_
diff --git a/ash/system/chromeos/audio/tray_audio_chromeos.cc b/ash/system/chromeos/audio/tray_audio_chromeos.cc
deleted file mode 100644
index d15eb79..0000000
--- a/ash/system/chromeos/audio/tray_audio_chromeos.cc
+++ /dev/null
@@ -1,57 +0,0 @@
-// 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/chromeos/audio/tray_audio_chromeos.h"
-
-#include "ash/ash_switches.h"
-#include "ash/metrics/user_metrics_recorder.h"
-#include "ash/shell.h"
-#include "ash/system/audio/volume_view.h"
-#include "ash/system/chromeos/audio/audio_detailed_view.h"
-#include "ui/views/view.h"
-
-namespace ash {
-namespace internal {
-
-TrayAudioChromeOs::TrayAudioChromeOs(
-    SystemTray* system_tray,
-    system::TrayAudioDelegate* audio_delegate)
-    : TrayAudio(system_tray, audio_delegate),
-      audio_detail_view_(NULL) {
-}
-
-TrayAudioChromeOs::~TrayAudioChromeOs() {
-}
-
-void TrayAudioChromeOs::Update() {
-  TrayAudio::Update();
-
-  if (audio_detail_view_)
-    audio_detail_view_->Update();
-}
-
-views::View* TrayAudioChromeOs::CreateDetailedView(user::LoginStatus status) {
-  if (!ash::switches::ShowAudioDeviceMenu() || pop_up_volume_view_) {
-    volume_view_ = new tray::VolumeView(this, audio_delegate_, false);
-    return volume_view_;
-  } else {
-    Shell::GetInstance()->metrics()->RecordUserMetricsAction(
-        ash::UMA_STATUS_AREA_DETAILED_AUDIO_VIEW);
-    audio_detail_view_ =
-        new tray::AudioDetailedView(this, status);
-    return audio_detail_view_;
-  }
-}
-
-void TrayAudioChromeOs::DestroyDetailedView() {
-  if (audio_detail_view_) {
-    audio_detail_view_ = NULL;
-  } else if (volume_view_) {
-    volume_view_ = NULL;
-    pop_up_volume_view_ = false;
-  }
-}
-
-}  // namespace internal
-}  // namespace ash
diff --git a/ash/system/chromeos/audio/tray_audio_chromeos.h b/ash/system/chromeos/audio/tray_audio_chromeos.h
deleted file mode 100644
index 2235842..0000000
--- a/ash/system/chromeos/audio/tray_audio_chromeos.h
+++ /dev/null
@@ -1,42 +0,0 @@
-// 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.
-
-#ifndef ASH_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_CHROMEOS_H_
-#define ASH_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_CHROMEOS_H_
-
-#include "ash/ash_export.h"
-#include "ash/system/audio/tray_audio.h"
-
-namespace ash {
-
-namespace internal {
-
-namespace tray {
-class AudioDetailedView;
-}
-
-class ASH_EXPORT TrayAudioChromeOs : public TrayAudio {
- public:
-  explicit TrayAudioChromeOs(SystemTray* system_tray,
-                             system::TrayAudioDelegate* audio_delegate);
-  virtual ~TrayAudioChromeOs();
-
- protected:
-  // Overridden from TrayAudio
-  virtual void Update() OVERRIDE;
-
- private:
-  // Overridden from SystemTrayItem.
-  virtual views::View* CreateDetailedView(user::LoginStatus status) OVERRIDE;
-  virtual void DestroyDetailedView() OVERRIDE;
-
-  tray::AudioDetailedView* audio_detail_view_;
-
-  DISALLOW_COPY_AND_ASSIGN(TrayAudioChromeOs);
-};
-
-}  // namespace internal
-}  // namespace ash
-
-#endif  // ASH_SYSTEM_CHROMEOS_AUDIO_TRAY_AUDIO_CHROMEOS_H_
diff --git a/ash/system/chromeos/audio/tray_audio_delegate_chromeos.cc b/ash/system/chromeos/audio/tray_audio_delegate_chromeos.cc
deleted file mode 100644
index 59f6ecf..0000000
--- a/ash/system/chromeos/audio/tray_audio_delegate_chromeos.cc
+++ /dev/null
@@ -1,65 +0,0 @@
-// 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/chromeos/audio/tray_audio_delegate_chromeos.h"
-
-#include "chromeos/audio/cras_audio_handler.h"
-#include "grit/ash_resources.h"
-#include "grit/ash_strings.h"
-
-using chromeos::CrasAudioHandler;
-
-namespace ash  {
-namespace system {
-
-void TrayAudioDelegateChromeOs::AdjustOutputVolumeToAudibleLevel() {
-  CrasAudioHandler::Get()->AdjustOutputVolumeToAudibleLevel();
-}
-
-int TrayAudioDelegateChromeOs::GetOutputDefaultVolumeMuteLevel() {
-  return CrasAudioHandler::Get()->GetOutputDefaultVolumeMuteThreshold();
-}
-
-int TrayAudioDelegateChromeOs::GetOutputVolumeLevel() {
-  return CrasAudioHandler::Get()->GetOutputVolumePercent();
-}
-
-int TrayAudioDelegateChromeOs::GetActiveOutputDeviceIconId() {
-  chromeos::AudioDevice device;
-  if (!CrasAudioHandler::Get()->GetActiveOutputDevice(&device))
-    return kNoAudioDeviceIcon;
-
-  if (device.type == chromeos::AUDIO_TYPE_HEADPHONE)
-    return IDR_AURA_UBER_TRAY_AUDIO_HEADPHONE;
-  else if (device.type == chromeos::AUDIO_TYPE_USB)
-    return IDR_AURA_UBER_TRAY_AUDIO_USB;
-  else if (device.type == chromeos::AUDIO_TYPE_BLUETOOTH)
-    return IDR_AURA_UBER_TRAY_AUDIO_BLUETOOTH;
-  else if (device.type == chromeos::AUDIO_TYPE_HDMI)
-    return IDR_AURA_UBER_TRAY_AUDIO_HDMI;
-  else
-    return kNoAudioDeviceIcon;
-}
-
-
-bool TrayAudioDelegateChromeOs::HasAlternativeSources() {
-  CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
-  return (audio_handler->has_alternative_output() ||
-          audio_handler->has_alternative_input());
-}
-
-bool TrayAudioDelegateChromeOs::IsOutputAudioMuted() {
-  return CrasAudioHandler::Get()->IsOutputMuted();
-}
-
-void TrayAudioDelegateChromeOs::SetOutputAudioIsMuted(bool is_muted) {
-  CrasAudioHandler::Get()->SetOutputMute(is_muted);
-}
-
-void TrayAudioDelegateChromeOs::SetOutputVolumeLevel(int level) {
-  CrasAudioHandler::Get()->SetOutputVolumePercent(level);
-}
-
-}  // namespace system
-}  // namespace ash
diff --git a/ash/system/chromeos/audio/tray_audio_delegate_chromeos.h b/ash/system/chromeos/audio/tray_audio_delegate_chromeos.h
deleted file mode 100644
index 58e714d..0000000
--- a/ash/system/chromeos/audio/tray_audio_delegate_chromeos.h
+++ /dev/null
@@ -1,33 +0,0 @@
-// 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.
-
-#ifndef ASH_SYSTEM_AUDIO_TRAY_AUDIO_DELEGATE_CHROMEOS_H_
-#define ASH_SYSTEM_AUDIO_TRAY_AUDIO_DELEGATE_CHROMEOS_H_
-
-#include "ash/ash_export.h"
-#include "ash/system/audio/tray_audio_delegate.h"
-#include "base/compiler_specific.h"
-
-namespace ash {
-namespace system {
-
-class ASH_EXPORT TrayAudioDelegateChromeOs : public TrayAudioDelegate {
- public:
-  virtual ~TrayAudioDelegateChromeOs() {}
-
-  // Overridden from TrayAudioDelegate.
-  virtual void AdjustOutputVolumeToAudibleLevel() OVERRIDE;
-  virtual int GetOutputDefaultVolumeMuteLevel() OVERRIDE;
-  virtual int GetOutputVolumeLevel() OVERRIDE;
-  virtual int GetActiveOutputDeviceIconId() OVERRIDE;
-  virtual bool HasAlternativeSources() OVERRIDE;
-  virtual bool IsOutputAudioMuted() OVERRIDE;
-  virtual void SetOutputAudioIsMuted(bool is_muted) OVERRIDE;
-  virtual void SetOutputVolumeLevel(int level) OVERRIDE;
-};
-
-}  // namespace system
-}  // namespace ash
-
-#endif  // ASH_SYSTEM_AUDIO_TRAY_AUDIO_DELEGATE_CHROMEOS_H_