Suggested Articles can be dismissed

ios/chrome/browser/content_suggestions/content_suggestions_mediator.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/chrome/browser/content_suggestions/content_suggestions_mediator.h"
 
 #include "base/mac/bind_objc_block.h"
 #include "base/memory/ptr_util.h"
 #include "base/optional.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 115 matching lines @@
     (ContentSuggestionsSectionInformation*)sectionInfo;
 
 @end
 
 @implementation ContentSuggestionsMediator
 
 @synthesize contentService = _contentService;
 @synthesize dataSink = _dataSink;
 @synthesize sectionInformationByCategory = _sectionInformationByCategory;
 
+#pragma mark - Public
+
 - (instancetype)initWithContentService:
     (ntp_snippets::ContentSuggestionsService*)contentService {
   self = [super init];
   if (self) {
     _suggestionBridge =
         base::MakeUnique<ContentSuggestionsServiceBridge>(self, contentService);
     _contentService = contentService;
     _sectionInformationByCategory = [[NSMutableDictionary alloc] init];
   }
   return self;
 }
 
+- (void)dismissSuggestion:(ContentSuggestionIdentifier*)suggestionIdentifier {
+  ContentSuggestionsCategoryWrapper* categoryWrapper =
+      [self categoryWrapperForSectionInfo:suggestionIdentifier.sectionInfo];
+  ntp_snippets::ContentSuggestion::ID suggestion_id =
+      ntp_snippets::ContentSuggestion::ID([categoryWrapper category],
+                                          suggestionIdentifier.IDInSection);
+
+  self.contentService->DismissSuggestion(suggestion_id);
+}
+
 #pragma mark - ContentSuggestionsDataSource
 
 - (NSArray<ContentSuggestion*>*)allSuggestions {
   std::vector<ntp_snippets::Category> categories =
       self.contentService->GetCategories();
   NSMutableArray<ContentSuggestion*>* dataHolders = [NSMutableArray array];
   for (auto& category : categories) {
     if (self.contentService->GetCategoryStatus(category) !=
         ntp_snippets::CategoryStatus::AVAILABLE) {
       continue;
@@ skipping 84 matching lines @@
       wrapperWithCategory:category]] = sectionInfo;
 }
 
 - (ContentSuggestionsCategoryWrapper*)categoryWrapperForSectionInfo:
     (ContentSuggestionsSectionInformation*)sectionInfo {
   return [[self.sectionInformationByCategory allKeysForObject:sectionInfo]
       firstObject];
 }
 
 @end