Add a whole-app-list unit test.

ui/app_list/views/app_list_view.h

Index: ui/app_list/views/app_list_view.h
diff --git a/ui/app_list/views/app_list_view.h b/ui/app_list/views/app_list_view.h
index 83ac2d6b8c60474fa6e361bce2d6bd3df851546e..5cc91ad7b55507bb0effef2415455e1a9a9d9e61 100644
--- a/ui/app_list/views/app_list_view.h
+++ b/ui/app_list/views/app_list_view.h
@@ -5,6 +5,7 @@
 #ifndef UI_APP_LIST_VIEWS_APP_LIST_VIEW_H_
 #define UI_APP_LIST_VIEWS_APP_LIST_VIEW_H_
 
+#include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "ui/app_list/app_list_export.h"
@@ -98,7 +99,7 @@ class APP_LIST_EXPORT AppListView : public views::BubbleDelegateView,
   void RemoveObserver(AppListViewObserver* observer);
 
   // Set a callback to be called the next time any app list paints.
-  static void SetNextPaintCallback(void (*callback)());
+  void SetNextPaintCallback(const base::Closure& callback);
 
 #if defined(OS_WIN)
   HWND GetHWND() const;
@@ -151,6 +152,9 @@ class APP_LIST_EXPORT AppListView : public views::BubbleDelegateView,
   ObserverList<AppListViewObserver> observers_;
   scoped_ptr<HideViewAnimationObserver> animation_observer_;
 
+  // For UMA and testing. If non-null, triggered when the app list is painted.
+  base::Closure next_paint_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(AppListView);
 };