Add spinner UI to show bluetooth is discovering devices.

ash/system/tray/tray_views.cc

Index: ash/system/tray/tray_views.cc
diff --git a/ash/system/tray/tray_views.cc b/ash/system/tray/tray_views.cc
index 86d9f0514284f77ab558be1ab25f705eb472b59d..1975c441c7e39cd44d29c3969f2e7d70177914fe 100644
--- a/ash/system/tray/tray_views.cc
+++ b/ash/system/tray/tray_views.cc
@@ -14,6 +14,8 @@
 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/events/event.h"
 #include "ui/base/resource/resource_bundle.h"
+#include "ui/compositor/layer.h"
+#include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/image/image_skia.h"
@@ -24,6 +26,7 @@
 #include "ui/views/border.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/controls/label.h"
+#include "ui/views/controls/throbber.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/layout/fill_layout.h"
 #include "ui/views/layout/grid_layout.h"
@@ -40,6 +43,12 @@ const int kSpecialPopupRowHeight = 55;
 const int kTrayPopupLabelButtonPaddingHorizontal = 16;
 const int kTrayPopupLabelButtonPaddingVertical = 8;
 
+// Time in ms per throbber frame.
+const int kThrobberFrameMs = 50;
+
+// Duration for showing/hiding animation in milliseconds.
+const int kThrobberAnimationDurationMs = 200;
+
 const int kBarImagesActive[] = {
     IDR_SLIDER_ACTIVE_LEFT,
     IDR_SLIDER_ACTIVE_CENTER,
@@ -611,6 +620,67 @@ void TrayBarButtonWithTitle::UpdateButton(bool control_on) {
   image_->Update(control_on);
 }
 
+ThrobberView::ThrobberView() {
+  throbber_ = new views::SmoothedThrobber(kThrobberFrameMs);
+  throbber_->set_stop_delay_ms(kThrobberAnimationDurationMs);
+  throbber_->set_interactive(false);
+  AddChildView(throbber_);
+
+  SetPaintToLayer(true);
+  layer()->SetFillsBoundsOpaquely(false);
+  layer()->SetOpacity(0.0);
+}
+
+ThrobberView::~ThrobberView() {
+}
+
+gfx::Size ThrobberView::GetPreferredSize() {
+  return gfx::Size(ash::kTrayPopupItemHeight, ash::kTrayPopupItemHeight);
+}
+
+void ThrobberView::Layout() {
+  View* child = child_at(0);
+  gfx::Size ps = child->GetPreferredSize();
+  child->SetBounds((width() - ps.width()) / 2,
+                   (height() - ps.height()) / 2,
+                   ps.width(), ps.height());
+  SizeToPreferredSize();
+}
+
+bool ThrobberView::GetTooltipText(const gfx::Point& p,
+                                  string16* tooltip) const {
+  if (tooltip_text_.empty())
+    return false;
+
+  *tooltip = tooltip_text_;
+  return true;
+}
+
+void ThrobberView::Start() {
+  ScheduleAnimation(true);
+  throbber_->Start();
+}
+
+void ThrobberView::Stop() {
+  ScheduleAnimation(false);
+  throbber_->Stop();
+}
+
+void ThrobberView::SetTooltipText(const string16& tooltip_text) {
+  tooltip_text_ = tooltip_text;
+}
+
+void ThrobberView::ScheduleAnimation(bool start_throbber) {
+  // Stop any previous animation.
+  layer()->GetAnimator()->StopAnimating();
+
+  ui::ScopedLayerAnimationSettings animation(layer()->GetAnimator());
+  animation.SetTransitionDuration(
+      base::TimeDelta::FromMilliseconds(kThrobberAnimationDurationMs));
+
+  layer()->SetOpacity(start_throbber ? 1.0 : 0.0);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // SpecialPopupRow
 
@@ -669,6 +739,15 @@ void SpecialPopupRow::AddButton(TrayPopupHeaderButton* button) {
   button_container_->AddChildView(button);
 }
 
+void SpecialPopupRow::AddThrobber(ThrobberView* throbber) {
+  if (!button_container_) {
+    button_container_ = CreatePopupHeaderButtonsContainer();
+    AddChildView(button_container_);
+  }
+
+  button_container_->AddChildView(throbber);
+}
+
 gfx::Size SpecialPopupRow::GetPreferredSize() {
   gfx::Size size = views::View::GetPreferredSize();
   size.set_height(kSpecialPopupRowHeight);