ContentSuggestions collection adds items with animation

ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.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_CONTENT_SUGGESTIONS_CONTENT_SUGGESTIONS_COLLECTION_UPDATER_H_
 #define IOS_CHROME_BROWSER_UI_CONTENT_SUGGESTIONS_CONTENT_SUGGESTIONS_COLLECTION_UPDATER_H_
 
 #import <UIKit/UIKit.h>
 
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestion.h"
@@ skipping 16 matching lines @@
 // adding items.
 @property(nonatomic, assign)
     ContentSuggestionsViewController* collectionViewController;
 
 // Returns whether the section should use the default, non-card style.
 - (BOOL)shouldUseCustomStyleForSection:(NSInteger)section;
 
 // Returns the ContentSuggestionType associated with this item.
 - (ContentSuggestionType)contentSuggestionTypeForItem:(CollectionViewItem*)item;
 
+// Adds the |suggestions| to the model and returns their index paths.
+- (NSArray<NSIndexPath*>*)addSuggestionsToModel:

[lpromero, 2017/03/14 16:23:01]

Either remove "toModel" here or add it to the second method. Would it make sense
to move the second method above this one?

If someone calls -addSuggestionsToModel:, does it create the sections if they
don't exist? Or does one ensures first to call -addSectionsForSuggestions:?

[gambard, 2017/03/15 10:03:41]

You should call -addSectionForSuggestions: first. I have added a comment.
Added ToModel to the method name.

+    (NSArray<ContentSuggestion*>*)suggestions;
+
+// Adds the sections for the |suggestions| to the model and returns their index.
+- (NSIndexSet*)addSectionsForSuggestions:
+    (NSArray<ContentSuggestion*>*)suggestions;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_CONTENT_SUGGESTIONS_CONTENT_SUGGESTIONS_COLLECTION_UPDATER_H_