Removed NativeAppsCollectionViewController and related code.

ios/chrome/browser/ui/settings/cells/native_app_item.h

-// Copyright 2016 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 IOS_CHROME_BROWSER_UI_SETTINGS_CELLS_NATIVE_APP_ITEM_H_
-#define IOS_CHROME_BROWSER_UI_SETTINGS_CELLS_NATIVE_APP_ITEM_H_
-
-#import <UIKit/UIKit.h>
-
-#import "ios/chrome/browser/ui/collection_view/cells/collection_view_item.h"
-#import "ios/third_party/material_components_ios/src/components/CollectionCells/src/MaterialCollectionCells.h"
-
-@class MDCButton;
-
-typedef NS_ENUM(NSInteger, NativeAppItemState) {
-  NativeAppItemSwitchOff,
-  NativeAppItemSwitchOn,
-  NativeAppItemInstall,
-};
-
-// Item to display and interact with a Native App.
-@interface NativeAppItem : CollectionViewItem
-
-// The display name of the app.
-@property(nonatomic, copy) NSString* name;
-
-// The icon of the app.
-@property(nonatomic, strong) UIImage* icon;
-
-// The state of the item:
-// - NativeAppItemSwitchOff: displays a switch set to OFF;
-// - NativeAppItemSwitchOn: displays a switch set to ON;
-// - NativeAppItemInstall: displays an INSTALL button;
-@property(nonatomic, assign) NativeAppItemState state;
-
-@end
-
-// Cell class associated to NativeAppItem.
-@interface NativeAppCell : MDCCollectionViewCell
-
-// Label for the app name.
-@property(nonatomic, strong, readonly) UILabel* nameLabel;
-
-// Image view for the app icon.
-@property(nonatomic, strong, readonly) UIImageView* iconImageView;
-
-// Accessory controls. switchControl is available after calling
-// -updateWithState: with NativeAppItemSwitch{On|Off}, while installButton is
-// available after calling -updateWithState: with NativeAppItemInstall.
-@property(nonatomic, strong, readonly) UISwitch* switchControl;
-@property(nonatomic, strong, readonly) MDCButton* installButton;
-
-// Updates the accessory view according to the given |state|.
-- (void)updateWithState:(NativeAppItemState)state;
-
-@end
-
-#endif  // IOS_CHROME_BROWSER_UI_SETTINGS_CELLS_NATIVE_APP_ITEM_H_