[ios clean] Add placeholder for NTP bookmarks, chrome home and open tabs.

ios/clean/chrome/browser/ui/bookmarks/bookmarks_coordinator.mm

+// Copyright 2017 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.
+
+#import "ios/clean/chrome/browser/ui/bookmarks/bookmarks_coordinator.h"
+
+#import "ios/chrome/browser/ui/bookmarks/bookmark_controller_factory.h"
+#import "ios/chrome/browser/ui/bookmarks/bookmark_home_handset_view_controller.h"
+#import "ios/chrome/browser/ui/bookmarks/bookmark_home_tablet_ntp_controller.h"
+#include "ios/chrome/browser/ui/ui_util.h"
+#import "ios/shared/chrome/browser/ui/browser_list/browser.h"
+#import "ios/shared/chrome/browser/ui/coordinators/browser_coordinator+internal.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@interface BookmarksCoordinator ()
+@property(nonatomic, strong) UIViewController* viewController;
+@property(nonatomic, strong) BookmarkHomeTabletNTPController* wrapperController;
+@end
+
+@implementation BookmarksCoordinator
+@synthesize viewController = _viewController;
+@synthesize wrapperController = _wrapperController;
+
+- (void)start {
+  // HACK: Re-using old view controllers for now.
+  if (!IsIPadIdiom()) {
+    self.viewController = [[BookmarkHomeHandsetViewController alloc]
+        initWithLoader:nil
+          browserState:self.browser->browser_state()];
+    self.viewController.modalPresentationStyle = UIModalPresentationFormSheet;
+  } else {
+    BookmarkControllerFactory* factory =
+        [[BookmarkControllerFactory alloc] init];
+    self.wrapperController = [factory
+        bookmarkPanelControllerForBrowserState:self.browser->browser_state()
+                                        loader:nil
+                                    colorCache:nil];
+    self.viewController = [[UIViewController alloc] init];
+    self.viewController.view = [self.wrapperController view];
+  }
+  [super start];
+}
+
+@end