Drag and drop between app list and launcher - First patch

ash/wm/app_list_controller.h

Index: ash/wm/app_list_controller.h
diff --git a/ash/wm/app_list_controller.h b/ash/wm/app_list_controller.h
index d2408d8bac4afba0be8384b8eb541311b07a71eb..6f05d6a97dd784453204f36504f9d1b46bb8d2b9 100644
--- a/ash/wm/app_list_controller.h
+++ b/ash/wm/app_list_controller.h
@@ -19,6 +19,7 @@
 #include "ui/views/widget/widget_observer.h"
 
 namespace app_list {
+class ApplicationDragAndDropHost;
 class AppListView;
 class PaginationModel;
 }
@@ -61,6 +62,11 @@ class AppListController : public ui::EventHandler,
   // Returns app list window or NULL if it is not visible.
   aura::Window* GetWindow();
 
+  // If |drag_and_drop_host| is not NULL it will be called upon drag and drop
+  // operations outside the application list.
+  void SetDragAndDropHostOfCurrentAppList(

[koz (OOO until 15th September), 2013/05/08 02:00:39]

Could you rename this to SetDragAndDropHost()? I think the "OfCurrentAppList"
bit is implied, eg: SetVisible() is implicitly talking about the current app
list.

[Mr4D (OOO till 08-26), 2013/05/08 02:53:35]

I did this because of my previous reviewer asked me to. His reasoning is that it
is clear that the association has to be set to the current object (every time)
since the object might go away AND the object needs first to be created before
it can be set.

+      app_list::ApplicationDragAndDropHost* drag_and_drop_host);
+
  private:
   // Sets the app list view and attempts to show it.
   void SetView(app_list::AppListView* view);