Add a11y virtual keyboard icon when a11y VK is enabled

ash/system/virtual_keyboard/virtual_keyboard_tray.cc

Index: ash/system/virtual_keyboard/virtual_keyboard_tray.cc
diff --git a/ash/system/virtual_keyboard/virtual_keyboard_tray.cc b/ash/system/virtual_keyboard/virtual_keyboard_tray.cc
new file mode 100644
index 0000000000000000000000000000000000000000..231c55b977439b8418a92c8400e344e240dab03c
--- /dev/null
+++ b/ash/system/virtual_keyboard/virtual_keyboard_tray.cc
@@ -0,0 +1,115 @@
+// 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/virtual_keyboard/virtual_keyboard_tray.h"
+
+#include "ash/shell.h"
+#include "ash/system/status_area_widget.h"
+#include "ash/system/tray/system_tray_notifier.h"
+#include "ash/system/tray/tray_constants.h"
+#include "ash/system/tray/tray_utils.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/events/event.h"
+#include "ui/gfx/image/image_skia.h"
+#include "ui/keyboard/keyboard_controller.h"
+#include "ui/views/controls/button/image_button.h"
+
+namespace ash {
+namespace internal {
+
+namespace {
+
+class VirtualKeyboardButton : public views::ImageButton {
+ public:
+  VirtualKeyboardButton(views::ButtonListener* listener);
+  virtual ~VirtualKeyboardButton();
+
+  // Overridden from views::ImageButton:
+  virtual gfx::Size GetPreferredSize() OVERRIDE;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(VirtualKeyboardButton);
+};
+
+}  // namespace
+
+VirtualKeyboardButton::VirtualKeyboardButton(views::ButtonListener* listener)
+    : views::ImageButton(listener) {
+}
+
+VirtualKeyboardButton::~VirtualKeyboardButton() {
+}
+
+gfx::Size VirtualKeyboardButton::GetPreferredSize() {
+  const int virtual_keyboard_button_size = GetShelfItemHeight();
+  return gfx::Size(virtual_keyboard_button_size, virtual_keyboard_button_size);
+}
+
+VirtualKeyboardTray::VirtualKeyboardTray(StatusAreaWidget* status_area_widget)
+    : TrayBackgroundView(status_area_widget),
+      button_(NULL) {
+  button_ = new VirtualKeyboardButton(this);
+  button_->SetImage(views::CustomButton::STATE_NORMAL,
+                    ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
+                        IDR_AURA_UBER_TRAY_VIRTUAL_KEYBOARD));
+  button_->SetImageAlignment(views::ImageButton::ALIGN_CENTER,
+                             views::ImageButton::ALIGN_MIDDLE);
+
+  tray_container()->AddChildView(button_);
+  SetContentsBackground();
+  // The Shell may not exist in some unit tests.
+  if (Shell::HasInstance()) {
+    Shell::GetInstance()->system_tray_notifier()->
+        AddAccessibilityObserver(this);
+  }
+}
+
+VirtualKeyboardTray::~VirtualKeyboardTray() {
+  // The Shell may not exist in some unit tests.
+  if (Shell::HasInstance()) {
+    Shell::GetInstance()->system_tray_notifier()->
+        RemoveAccessibilityObserver(this);
+  }
+}
+
+void VirtualKeyboardTray::SetShelfAlignment(ShelfAlignment alignment) {
+  TrayBackgroundView::SetShelfAlignment(alignment);
+  tray_container()->SetBorder(views::Border::NullBorder());
+}
+
+base::string16 VirtualKeyboardTray::GetAccessibleNameForTray() {
+  return l10n_util::GetStringUTF16(
+      IDS_ASH_VIRTUAL_KEYBOARD_TRAY_ACCESSIBLE_NAME);
+}
+
+void VirtualKeyboardTray::HideBubbleWithView(
+    const views::TrayBubbleView* bubble_view) {
+}
+
+bool VirtualKeyboardTray::ClickedOutsideBubble() {
+  return false;
+}
+
+bool VirtualKeyboardTray::PerformAction(const ui::Event& event) {
+  Shell::GetInstance()->keyboard_controller()->ShowAndLockKeyboard();
+  return true;
+}
+
+void VirtualKeyboardTray::ButtonPressed(views::Button* sender,
+                                        const ui::Event& event) {
+  DCHECK_EQ(button_, sender);
+  PerformAction(event);
+}
+
+void VirtualKeyboardTray::OnAccessibilityModeChanged(
+    AccessibilityNotificationVisibility notify) {
+  SetVisible(Shell::GetInstance()->accessibility_delegate()->
+      IsVirtualKeyboardEnabled());
+}
+
+}  // namespace internal
+}  // namespace ash