Add long press actions for Most Visited tiles

ios/chrome/browser/content_suggestions/content_suggestions_mediator.h

 // 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.
 
 #ifndef IOS_CHROME_BROWSER_CONTENT_SUGGESTIONS_CONTENT_SUGGESTIONS_MEDIATOR_H_
 #define IOS_CHROME_BROWSER_CONTENT_SUGGESTIONS_CONTENT_SUGGESTIONS_MEDIATOR_H_
 
 #import <UIKit/UIKit.h>
 
 #include <memory>
 
 #import "ios/chrome/browser/content_suggestions/content_suggestions_mediator.h"
 #import "ios/chrome/browser/ui/content_suggestions/content_suggestions_data_source.h"
 
 namespace favicon {
 class LargeIconService;
 }
 
 namespace ntp_snippets {
 class ContentSuggestionsService;
 }
 
 namespace ntp_tiles {
 class MostVisitedSites;
 }
 
 @protocol ContentSuggestionsCommands;
 @class ContentSuggestionIdentifier;
+class GURL;
 
 // Mediator for ContentSuggestions. Makes the interface between a
 // ntp_snippets::ContentSuggestionsService and the Objective-C services using
 // its data.
 @interface ContentSuggestionsMediator : NSObject<ContentSuggestionsDataSource>
 
 // Initialize the mediator with the |contentService| to mediate.
 - (nullable instancetype)
 initWithContentService:
     (nonnull ntp_snippets::ContentSuggestionsService*)contentService
       largeIconService:(nonnull favicon::LargeIconService*)largeIconService
        mostVisitedSite:
            (std::unique_ptr<ntp_tiles::MostVisitedSites>)mostVisitedSites
     NS_DESIGNATED_INITIALIZER;
 
 - (nullable instancetype)init NS_UNAVAILABLE;
 
 // Command handler for the mediator.
 @property(nonatomic, weak, nullable) id<ContentSuggestionsCommands>
     commandHandler;
 
 // Dismisses the suggestion from the content suggestions service. It doesn't
 // change the UI.
 - (void)dismissSuggestion:
     (nonnull ContentSuggestionIdentifier*)suggestionIdentifier;
 
+// Blacklists the URL from the Most Visited sites.
+- (void)blacklistMostVisitedURL:(GURL)URL;
+
+// Whitelists the URL from the Most Visited sites.
+- (void)whitelistMostVisitedURL:(GURL)URL;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_CONTENT_SUGGESTIONS_CONTENT_SUGGESTIONS_MEDIATOR_H_