Make GetDismissedSuggestionsForDebugging asynchronous

components/ntp_snippets/content_suggestions_service_unittest.cc

 // 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.
 
 #include "components/ntp_snippets/content_suggestions_service.h"
 
 #include <memory>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 82 matching lines @@
     statuses_[category.id()] = new_status;
     observer()->OnCategoryStatusChanged(this, category, new_status);
   }
 
   void FireSuggestionInvalidated(Category category,
                                  const std::string& suggestion_id) {
     observer()->OnSuggestionInvalidated(this, category, suggestion_id);
   }
 
   MOCK_METHOD1(ClearCachedSuggestionsForDebugging, void(Category category));
-  MOCK_METHOD1(GetDismissedSuggestionsForDebugging,
-               std::vector<ContentSuggestion>(Category category));
+  MOCK_METHOD2(GetDismissedSuggestionsForDebugging,
+               void(Category category,
+                    const DismissedSuggestionsCallback& callback));
   MOCK_METHOD1(ClearDismissedSuggestionsForDebugging, void(Category category));
   MOCK_METHOD1(DismissSuggestion, void(const std::string& suggestion_id));
   MOCK_METHOD2(FetchSuggestionImage,
                void(const std::string& suggestion_id,
                     const ImageFetchedCallback& callback));
 
  private:
   std::vector<Category> provided_categories_;
   std::map<int, CategoryStatus> statuses_;
 };
@@ skipping 382 matching lines @@
 
   EXPECT_THAT(service()->GetCategoryStatus(category),
               Eq(CategoryStatus::NOT_PROVIDED));
   EXPECT_TRUE(service()->GetCategories().empty());
   ExpectThatSuggestionsAre(category, std::vector<int>());
 
   service()->RemoveObserver(&observer);
 }
 
 }  // namespace ntp_snippets