Add unit tests for screen capture and share notification UI.

ash/system/chromeos/screen_security/screen_capture_tray_item.h

 // Copyright 2013 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_SCREEN_CAPTURE_SCREEN_CAPTURE_TRAY_ITEM_H_
 #define ASH_SYSTEM_CHROMEOS_SCREEN_CAPTURE_SCREEN_CAPTURE_TRAY_ITEM_H_
 
 #include "ash/system/chromeos/screen_security/screen_capture_observer.h"
 #include "ash/system/chromeos/screen_security/screen_tray_item.h"
 
 namespace views {
 class View;
 }
 
 namespace ash {
 namespace internal {
 
-class ScreenCaptureTrayItem : public ScreenTrayItem,
-                              public ScreenCaptureObserver {
+class ASH_EXPORT ScreenCaptureTrayItem : public ScreenTrayItem,
+                                         public ScreenCaptureObserver {
  public:
   explicit ScreenCaptureTrayItem(SystemTray* system_tray);
   virtual ~ScreenCaptureTrayItem();
 
  private:
   // Overridden from ScreenTrayItem.
   virtual views::View* CreateTrayView(user::LoginStatus status) OVERRIDE;
   virtual views::View* CreateDefaultView(user::LoginStatus status) OVERRIDE;
   virtual views::View* CreateNotificationView(
       user::LoginStatus status) OVERRIDE;
 
   // Overridden from ScreenCaptureObserver.
   virtual void OnScreenCaptureStart(
       const base::Closure& stop_callback,
       const base::string16& screen_capture_status) OVERRIDE;
   virtual void OnScreenCaptureStop() OVERRIDE;
 
   base::string16 screen_capture_status_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenCaptureTrayItem);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_CHROMEOS_SCREEN_CAPTURE_SCREEN_CAPTURE_TRAY_ITEM_H_