Allow CollectionViewModel/Controller queries without SectionIdentifier

ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.mm

 // 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.
 
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.h"
 
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/time/time.h"
@@ skipping 166 matching lines @@
     if (item.suggestionIdentifier == suggestionIdentifier) {
       correspondingItem = item;
       break;
     }
   }
 
   if (!correspondingItem)
     return;
 
   NSIndexPath* indexPath = [self.collectionViewController.collectionViewModel
-             indexPathForItem:correspondingItem
-      inSectionWithIdentifier:sectionIdentifier];
+      indexPathForItem:correspondingItem];
   [self.collectionViewController dismissEntryAtIndexPath:indexPath];
 }
 
 - (void)reloadAllData {
   [self resetModels];
 
   // The data is reset, add the new data directly in the model then reload the
   // collection.
   NSArray<ContentSuggestion*>* suggestions = [self.dataSource allSuggestions];
   [self addSectionsForSuggestionsToModel:suggestions];
@@ skipping 133 matching lines @@
   ContentSuggestionsSectionInformation* sectionInfo =
       self.sectionInfoBySectionIdentifier[@(sectionIdentifier)];
 
   CSCollectionViewItem* item = [self emptyItemForSectionInfo:sectionInfo];
   return [self addItem:item toSectionWithIdentifier:sectionIdentifier];
 }
 
 #pragma mark - ContentSuggestionsArticleItemDelegate
 
 - (void)loadImageForArticleItem:(ContentSuggestionsArticleItem*)articleItem {
-  NSInteger sectionIdentifier =
-      SectionIdentifierForInfo(articleItem.suggestionIdentifier.sectionInfo);
-
   __weak ContentSuggestionsCollectionUpdater* weakSelf = self;
   __weak ContentSuggestionsArticleItem* weakArticle = articleItem;
 
   void (^imageFetchedCallback)(UIImage*) = ^(UIImage* image) {
     ContentSuggestionsCollectionUpdater* strongSelf = weakSelf;
     ContentSuggestionsArticleItem* strongArticle = weakArticle;
     if (!strongSelf || !strongArticle) {
       return;
     }
 
     strongArticle.image = image;
     [strongSelf.collectionViewController
-        reconfigureCellsForItems:@[ strongArticle ]
-         inSectionWithIdentifier:sectionIdentifier];
+        reconfigureCellsForItems:@[ strongArticle ]];
   };
 
   [self.dataSource.imageFetcher
       fetchImageForSuggestion:articleItem.suggestionIdentifier
                      callback:imageFetchedCallback];
 }
 
 #pragma mark - Private methods
 
 // Adds a footer to the section identified by |sectionInfo| if there is none
@@ skipping 109 matching lines @@
 
   __weak ContentSuggestionsCollectionUpdater* weakSelf = self;
   [self.dataSource
       fetchFaviconImageForSuggestion:articleItem.suggestionIdentifier
                           completion:^void(UIImage* favicon) {
                             if (!weakItem || !weakSelf)
                               return;
 
                             weakItem.attributes =
                                 [FaviconAttributes attributesWithImage:favicon];
-                            [weakSelf reconfigure:weakItem];
+                            [weakSelf.collectionViewController
+                                reconfigureCellsForItems:@[ weakItem ]];
                           }];
 
   return articleItem;
 }
 
 // Returns a reading list item built with the |suggestion|.
 - (ContentSuggestionsReadingListItem*)readingListItemForSuggestion:
     (ContentSuggestion*)suggestion {
   ContentSuggestionsReadingListItem* readingListItem =
       [[ContentSuggestionsReadingListItem alloc]
@@ skipping 29 matching lines @@
   void (^completionBlock)(FaviconAttributes* attributes) =
       ^(FaviconAttributes* attributes) {
         CSCollectionViewItem* strongItem = weakItem;
         ContentSuggestionsCollectionUpdater* strongSelf = weakSelf;
         if (!strongSelf || !strongItem) {
           return;
         }
 
         callback(attributes);
 
-        [strongSelf reconfigure:strongItem];
+        [strongSelf.collectionViewController
+            reconfigureCellsForItems:@[ strongItem ]];
       };
 
   [self.dataSource fetchFaviconAttributesForURL:URL completion:completionBlock];
 }
 
 // Adds |item| to |sectionIdentifier| section of the model of the
 // CollectionView. Returns the IndexPath of the newly added item.
 - (NSIndexPath*)addItem:(CSCollectionViewItem*)item
     toSectionWithIdentifier:(NSInteger)sectionIdentifier {
   CSCollectionViewModel* model =
       self.collectionViewController.collectionViewModel;
   NSInteger section = [model sectionForSectionIdentifier:sectionIdentifier];
   NSInteger itemNumber = [model numberOfItemsInSection:section];
   [model addItem:item toSectionWithIdentifier:sectionIdentifier];
 
   return [NSIndexPath indexPathForItem:itemNumber inSection:section];
 }
 
-// Reconfigures the |item| in the collection view.
-- (void)reconfigure:(CSCollectionViewItem*)item {
-  CSCollectionViewModel* model =
-      self.collectionViewController.collectionViewModel;
-
-  for (NSInteger sectionNumber = 0; sectionNumber < [model numberOfSections];
-       sectionNumber++) {
-    NSInteger sectionIdentifier =
-        [model sectionIdentifierForSection:sectionNumber];
-    if ([model hasItem:item inSectionWithIdentifier:sectionIdentifier]) {
-      [self.collectionViewController
-          reconfigureCellsForItems:@[ item ]
-           inSectionWithIdentifier:sectionIdentifier];
-    }
-  }
-}
-
 @end