Revert of Draggable peeking/fullscreen launcher with transparent background.

ui/app_list/views/all_apps_tile_item_view.h

Index: ui/app_list/views/all_apps_tile_item_view.h
diff --git a/ui/app_list/views/all_apps_tile_item_view.h b/ui/app_list/views/all_apps_tile_item_view.h
index aa5235148d7a4ef9e248a002b0ad41a9a9329f28..a3cf94b987fa92496763b91eccaf6935e0bdd60b 100644
--- a/ui/app_list/views/all_apps_tile_item_view.h
+++ b/ui/app_list/views/all_apps_tile_item_view.h
@@ -11,13 +11,12 @@
 
 namespace app_list {
 
-class AppListView;
 class ContentsView;
 
 // A tile item for the "All apps" button on the start page.
 class AllAppsTileItemView : public TileItemView {
  public:
-  AllAppsTileItemView(ContentsView* contents_view, AppListView* app_list_view);
+  explicit AllAppsTileItemView(ContentsView* contents_view);
 
   ~AllAppsTileItemView() override;
 
@@ -28,7 +27,6 @@
 
  private:
   ContentsView* contents_view_;
-  AppListView* const app_list_view_;  // Owned by the views hierarchy.
 
   DISALLOW_COPY_AND_ASSIGN(AllAppsTileItemView);
 };