[NTP Snippets] Persist non-article remote suggestions in the DB

components/ntp_snippets/remote/ntp_snippets_service_unittest.cc

 // Copyright 2015 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/remote/ntp_snippets_service.h"
 
 #include <memory>
 #include <utility>
 #include <vector>
 
@@ skipping 762 matching lines @@
 
   CategoryInfo info_articles_after =
       service->GetCategoryInfo(articles_category());
   CategoryInfo info_unknown_after =
       service->GetCategoryInfo(unknown_category());
 
   EXPECT_EQ(info_articles_before.title(), info_articles_after.title());
   EXPECT_EQ(info_unknown_before.title(), info_unknown_after.title());
 }
 
+TEST_F(NTPSnippetsServiceTest, PersistSuggestions) {
+  auto service = MakeSnippetsService();
+
+  LoadFromJSONString(service.get(),
+                     GetMultiCategoryJson({GetSnippetN(0)}, {GetSnippetN(1)}));
+
+  ASSERT_THAT(service->GetSnippetsForTesting(articles_category()), SizeIs(1));
+  ASSERT_THAT(service->GetSnippetsForTesting(other_category()), SizeIs(1));
+
+  // Recreate the service to simulate a Chrome restart.
+  ResetSnippetsService(&service);
+
+  // The suggestions in both categories should have been restored.
+  EXPECT_THAT(service->GetSnippetsForTesting(articles_category()), SizeIs(1));
+  EXPECT_THAT(service->GetSnippetsForTesting(other_category()), SizeIs(1));
+}
+
 TEST_F(NTPSnippetsServiceTest, Clear) {
   auto service = MakeSnippetsService();
 
   std::string json_str(GetTestJson({GetSnippet()}));
 
   LoadFromJSONString(service.get(), json_str);
   EXPECT_THAT(service->GetSnippetsForTesting(articles_category()), SizeIs(1));
 
   service->ClearCachedSuggestions(articles_category());
   EXPECT_THAT(service->GetSnippetsForTesting(articles_category()), IsEmpty());
@@ skipping 479 matching lines @@
         base::StringPrintf("http://localhost/snippet-id-%d", i)));
   }
   LoadFromJSONString(service.get(), GetTestJson(suggestions));
   // TODO(tschumann): We should probably trim out any additional results and
   // only serve the MaxSnippetCount items.
   EXPECT_THAT(service->GetSnippetsForTesting(articles_category()),
               SizeIs(service->GetMaxSnippetCountForTesting() + 1));
 }
 
 }  // namespace ntp_snippets