Attempting to reland the Overview Button Change.

ash/system/overview/overview_button_tray.cc

Index: ash/system/overview/overview_button_tray.cc
diff --git a/ash/system/overview/overview_button_tray.cc b/ash/system/overview/overview_button_tray.cc
new file mode 100644
index 0000000000000000000000000000000000000000..4ca41668d8f050713dab76be5f83bf45806d7add
--- /dev/null
+++ b/ash/system/overview/overview_button_tray.cc
@@ -0,0 +1,106 @@
+// 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/overview/overview_button_tray.h"
+
+#include "ash/shelf/shelf_types.h"
+#include "ash/shell.h"
+#include "ash/system/tray/tray_utils.h"
+#include "ash/wm/overview/window_selector_controller.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/image_view.h"
+
+namespace {
+
+// Predefined padding for the icon used in this tray. These are to be set to the
+// border of the icon, depending on the current shelf_alignment()
+const int kHorizontalShelfHorizontalPadding = 8;
+const int kHorizontalShelfVerticalPadding = 4;
+const int kVerticalShelfHorizontalPadding = 2;
+const int kVerticalShelfVerticalPadding = 5;
+
+}  // namespace
+
+namespace ash {
+
+OverviewButtonTray::OverviewButtonTray(
+    internal::StatusAreaWidget* status_area_widget)
+    : TrayBackgroundView(status_area_widget),
+      icon_(NULL) {
+  SetContentsBackground();
+
+  ui::ResourceBundle& bundle = ui::ResourceBundle::GetSharedInstance();
+  icon_ = new views::ImageView();
+  icon_->SetImage(
+      bundle.GetImageNamed(IDR_AURA_UBER_TRAY_OVERVIEW_MODE).ToImageSkia());
+  SetIconBorderForShelfAlignment();
+  tray_container()->AddChildView(icon_);
+
+  SetVisible(Shell::GetInstance()->IsMaximizeModeWindowManagerEnabled());
+
+  Shell::GetInstance()->AddShellObserver(this);
+}
+
+OverviewButtonTray::~OverviewButtonTray() {
+  Shell::GetInstance()->RemoveShellObserver(this);
+}
+
+bool OverviewButtonTray::PerformAction(const ui::Event& event) {
+  Shell::GetInstance()->window_selector_controller()->ToggleOverview();
+  return true;
+}
+
+void OverviewButtonTray::OnMaximizeModeStarted() {
+  SetVisible(true);
+}
+
+void OverviewButtonTray::OnMaximizeModeEnded() {
+  SetVisible(false);
+}
+
+bool OverviewButtonTray::ClickedOutsideBubble() {
+  // This class has no bubbles dismiss, but acknowledge that the message was
+  // handled.
+  return true;
+}
+
+base::string16 OverviewButtonTray::GetAccessibleNameForTray() {
+  return l10n_util::GetStringUTF16(IDS_ASH_OVERVIEW_BUTTON_ACCESSIBLE_NAME);
+}
+
+void OverviewButtonTray::HideBubbleWithView(
+    const views::TrayBubbleView* bubble_view) {
+  // This class has no bubbles to hide.
+}
+
+void OverviewButtonTray::SetShelfAlignment(ShelfAlignment alignment) {
+  if (alignment == shelf_alignment())
+    return;
+
+  TrayBackgroundView::SetShelfAlignment(alignment);
+  SetIconBorderForShelfAlignment();
+}
+
+void OverviewButtonTray::SetIconBorderForShelfAlignment() {
+  if (shelf_alignment() == SHELF_ALIGNMENT_BOTTOM ||
+      shelf_alignment() == SHELF_ALIGNMENT_TOP) {
+    icon_->SetBorder(views::Border::CreateEmptyBorder(
+        kHorizontalShelfVerticalPadding,
+        kHorizontalShelfHorizontalPadding,
+        kHorizontalShelfVerticalPadding,
+        kHorizontalShelfHorizontalPadding));
+  } else {
+    icon_->SetBorder(views::Border::CreateEmptyBorder(
+        kVerticalShelfVerticalPadding,
+        kVerticalShelfHorizontalPadding,
+        kVerticalShelfVerticalPadding,
+        kVerticalShelfHorizontalPadding));
+  }
+}
+
+}  // namespace ash