Add a unit test for resetting the app list on a reshow.

ui/app_list/views/top_icon_animation_view.h

Index: ui/app_list/views/top_icon_animation_view.h
diff --git a/ui/app_list/views/top_icon_animation_view.h b/ui/app_list/views/top_icon_animation_view.h
index c50d1227256a0e5227a194fe04cbff23781c69f9..a5be43b7fbba48c226d270be7343364aa90cccf5 100644
--- a/ui/app_list/views/top_icon_animation_view.h
+++ b/ui/app_list/views/top_icon_animation_view.h
@@ -6,6 +6,7 @@
 #define UI_APP_LIST_VIEWS_TOP_ICON_ANIMATION_VIEW_H
 
 #include "base/observer_list.h"
+#include "ui/app_list/app_list_export.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/views/view.h"
 
@@ -16,7 +17,7 @@ class ImageView;
 namespace app_list {
 
 // Observer for top icon animation completion.
-class TopIconAnimationObserver {
+class APP_LIST_EXPORT TopIconAnimationObserver {
  public:
   // Called when top icon animation completes.
   virtual void OnTopIconAnimationsComplete() {}