Add spinner UI to show bluetooth is discovering devices.

ash/system/tray/tray_views.h

Index: ash/system/tray/tray_views.h
diff --git a/ash/system/tray/tray_views.h b/ash/system/tray/tray_views.h
index 4e7588dda1cb85d2a99dd8c31b2ecb8a83417b9a..6db419caaa1650c1a842e7d2b550181e8000b877 100644
--- a/ash/system/tray/tray_views.h
+++ b/ash/system/tray/tray_views.h
@@ -16,6 +16,7 @@
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/scroll_view.h"
 #include "ui/views/controls/slider.h"
+#include "ui/views/controls/throbber.h"
 #include "ui/views/view.h"
 
 typedef unsigned int SkColor;
@@ -271,6 +272,53 @@ class TrayBarButtonWithTitle : public views::CustomButton {
   DISALLOW_COPY_AND_ASSIGN(TrayBarButtonWithTitle);
 };
 
+// A SmoothedThrobber with tooltip.
+class SystemTrayThrobber : public views::SmoothedThrobber {
+ public:
+  SystemTrayThrobber(int frame_delay_ms);
+  virtual ~SystemTrayThrobber();
+
+  void SetTooltipText(const string16& tooltip_text);
+
+  // Overriden from views::View.
+  virtual bool GetTooltipText(
+        const gfx::Point& p, string16* tooltip) const OVERRIDE;
+
+ private:
+  // The current tooltip text.
+  string16 tooltip_text_;
+
+  DISALLOW_COPY_AND_ASSIGN(SystemTrayThrobber);
+};
+
+// A View containing a SystemTrayThrobber with animation for starting/stopping.
+class ThrobberView : public views::View {
+ public:
+  ThrobberView();
+  virtual ~ThrobberView();
+
+  void Start();
+  void Stop();
+  void SetTooltipText(const string16& tooltip_text);
+
+  // Overriden from views::View.
+  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual void Layout() OVERRIDE;
+  virtual bool GetTooltipText(
+      const gfx::Point& p, string16* tooltip) const OVERRIDE;
+
+ private:
+  // Schedules animation for starting/stopping throbber.
+  void ScheduleAnimation(bool start_throbber);
+
+  SystemTrayThrobber* throbber_;
+
+  // The current tooltip text.
+  string16 tooltip_text_;
+
+  DISALLOW_COPY_AND_ASSIGN(ThrobberView);
+};
+
 // The 'special' looking row in the uber-tray popups. This is usually the bottom
 // row in the popups, and has a fixed height.
 class SpecialPopupRow : public views::View {
@@ -282,6 +330,7 @@ class SpecialPopupRow : public views::View {
   void SetContent(views::View* view);
 
   void AddButton(TrayPopupHeaderButton* button);
+  void AddThrobber(ThrobberView* throbber);
 
   views::View* content() const { return content_; }