Add header for the Content Suggestions

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

Index: ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.mm
diff --git a/ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.mm b/ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.mm
index ee0f2048beb7027c49dbde1da124275bd466a787..8a5c799b81ad633714efe9a9310267a15beaa194 100644
--- a/ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.mm
+++ b/ios/chrome/browser/ui/content_suggestions/content_suggestions_collection_updater.mm
@@ -17,6 +17,7 @@
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_expandable_item.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_favicon_item.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_footer_item.h"
+#import "ios/chrome/browser/ui/content_suggestions/content_suggestions_header_item.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_image_fetcher.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_section_information.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_stack_item.h"
@@ -39,6 +40,7 @@ typedef NS_ENUM(NSInteger, ItemType) {
   ItemTypeStack,
   ItemTypeFavicon,
   ItemTypeFooter,
+  ItemTypeHeader,
 };
 
 typedef NS_ENUM(NSInteger, SectionIdentifier) {
@@ -166,8 +168,10 @@ SectionIdentifier SectionIdentifierForInfo(
 
 - (void)reloadAllData {
   [self resetModels];
-  [self.collectionViewController
-      addSuggestions:[self.dataSource allSuggestions]];
+  NSArray<ContentSuggestion*>* suggestions = [self.dataSource allSuggestions];
+  [self addSectionsForSuggestionsToModel:suggestions];
+  [self addSuggestionsToModel:suggestions];
+  [self.collectionViewController.collectionView reloadData];

[gambard, 2017/03/16 15:49:41]

This is a bug fix, appearing only when you add header.

[lpromero, 2017/03/16 16:43:21]

Can you explain more on the issue in a comment in the code?

[gambard, 2017/03/17 09:33:39]

Done.

 }
 
 - (void)clearSection:(ContentSuggestionsSectionInformation*)sectionInfo {
@@ -248,6 +252,7 @@ SectionIdentifier SectionIdentifierForInfo(
       [indexSet addIndex:[model sectionForSectionIdentifier:sectionIdentifier]];
 
       [self addFooterIfNeeded:suggestion.suggestionIdentifier.sectionInfo];
+      [self addHeader:suggestion.suggestionIdentifier.sectionInfo];

[lpromero, 2017/03/16 16:43:21]

Optional nit: move one line up?

[gambard, 2017/03/17 09:33:39]

Done.

     }
   }
   return indexSet;
@@ -307,6 +312,21 @@ SectionIdentifier SectionIdentifierForInfo(
   }
 }
 
+// Adds the header corresponding to |sectionInfo| to the section.
+- (void)addHeader:(ContentSuggestionsSectionInformation*)sectionInfo {
+  NSInteger sectionIdentifier = SectionIdentifierForInfo(sectionInfo);
+
+  if (![self.collectionViewController.collectionViewModel
+          headerForSectionWithIdentifier:sectionIdentifier]) {
+    ContentSuggestionsHeaderItem* header =
+        [[ContentSuggestionsHeaderItem alloc] initWithType:ItemTypeHeader];
+    header.text = sectionInfo.title;
+    [self.collectionViewController.collectionViewModel
+                       setHeader:header
+        forSectionWithIdentifier:sectionIdentifier];
+  }
+}
+
 // Resets the models, removing the current CollectionViewItem and the
 // SectionInfo.
 - (void)resetModels {