Add deprecation warning banner to App Launcher on Mac.

ui/app_list/cocoa/apps_grid_controller.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_APP_LIST_COCOA_APPS_GRID_CONTROLLER_H_
 #define UI_APP_LIST_COCOA_APPS_GRID_CONTROLLER_H_
 
 #import <Cocoa/Cocoa.h>
 #include <stddef.h>
 
@@ skipping 41 matching lines @@
 }
 
 @property(assign, nonatomic) id<AppsPaginationModelObserver> paginationObserver;
 
 + (void)setScrollAnimationDuration:(NSTimeInterval)duration;
 
 // The amount the grid view has been extended to hold the sometimes present
 // invisible scroller that allows for gesture scrolling.
 + (CGFloat)scrollerPadding;
 
+// Whether the grid is configured with fewer rows than normal.
++ (BOOL)hasFewerRows;
+
 - (NSCollectionView*)collectionViewAtPageIndex:(size_t)pageIndex;
 - (size_t)pageIndexForCollectionView:(NSCollectionView*)page;
 
 - (AppsGridViewItem*)itemAtIndex:(size_t)itemIndex;
 
 - (app_list::AppListModel*)model;
 
 - (void)setDelegate:(app_list::AppListViewDelegate*)newDelegate;
 
 - (size_t)visiblePage;
@@ skipping 42 matching lines @@
 @end
 
 @interface AppsGridController(TestingAPI)
 
 - (AppsCollectionViewDragManager*)dragManager;
 - (size_t)scheduledScrollPage;
 
 @end
 
 #endif  // UI_APP_LIST_COCOA_APPS_GRID_CONTROLLER_H_