Remove old (dead) app list code.

ui/app_list/views/contents_view.h

Index: ui/app_list/views/contents_view.h
diff --git a/ui/app_list/views/contents_view.h b/ui/app_list/views/contents_view.h
index ba529403daf427126fb21a7528ab2ef50a9c6a95..c41702a98971c0b759fc70418be414a709dd902d 100644
--- a/ui/app_list/views/contents_view.h
+++ b/ui/app_list/views/contents_view.h
@@ -50,9 +50,8 @@ class APP_LIST_EXPORT ContentsView : public views::View,
   explicit ContentsView(AppListMainView* app_list_main_view);
   ~ContentsView() override;
 
-  // Initialize the pages of the launcher. In the experimental launcher, should
-  // be called after set_contents_switcher_view(), or switcher buttons will not
-  // be created.
+  // Initialize the pages of the launcher. Should be called after
+  // set_contents_switcher_view().
   void Init(AppListModel* model);
 
   // The app list gets closed and drag and drop operations need to be cancelled.
@@ -179,11 +178,9 @@ class APP_LIST_EXPORT ContentsView : public views::View,
   // launcher-page pagination.
   PaginationModel* GetAppsPaginationModel();
 
-  // Special sub views of the ContentsView. All owned by the views hierarchy.
+  // Sub-views of the ContentsView. All owned by the views hierarchy.
   AppsContainerView* apps_container_view_;
   SearchResultPageView* search_results_page_view_;
-
-  // Only used in the experimental app list.
   StartPageView* start_page_view_;
   CustomLauncherPageView* custom_page_view_;