Revert of Removing "All Bookmarks"

ios/chrome/browser/ui/bookmarks/bookmark_folder_collection_view.mm

 // Copyright 2014 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/chrome/browser/ui/bookmarks/bookmark_folder_collection_view.h"
 
 #include "base/logging.h"
 #include "base/mac/objc_property_releaser.h"
 #include "base/strings/sys_string_conversions.h"
 #include "components/bookmarks/browser/bookmark_model.h"
@@ skipping 421 matching lines @@
 - (void)collectionViewScrolled {
   [self.delegate bookmarkCollectionViewDidScroll:self];
 }
 
 - (void)setEditing:(BOOL)editing animated:(BOOL)animated {
   [super setEditing:editing animated:animated];
   [self promoStateChangedAnimated:animated];
 }
 
 - (void)promoStateChangedAnimated:(BOOL)animate {
+  if (experimental_flags::IsAllBookmarksEnabled())
+    return;  // The promo is not shown if All Bookmarks is enabled.
+
   BOOL newPromoState =
       !self.editing && self.folder &&
       self.folder->type() == BookmarkNode::MOBILE &&
       [self.delegate bookmarkCollectionViewShouldShowPromoCell:self];
   if (newPromoState != _promoVisible) {
     // This is awful, but until the old code to do the refresh when switching
     // in and out of edit mode is fixed, this is probably the cleanest thing to
     // do.
     _promoVisible = newPromoState;
     [self.collectionView reloadData];
@@ skipping 10 matching lines @@
   [self.delegate bookmarkCollectionViewDismissPromo:self];
 }
 
 #pragma mark - Promo Cell
 
 - (BOOL)shouldShowPromoCell {
   return _promoVisible;
 }
 
 @end