Various NTPSnippetsService cleanups:

components/ntp_snippets/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/ntp_snippets_service.h"
 
 #include <memory>
 #include <vector>
 
 #include "base/command_line.h"
@@ skipping 204 matching lines @@
         fake_signin_manager_(new FakeSigninManagerBase(signin_client_.get(),
                                                        account_tracker_.get())),
         fake_token_service_(new FakeProfileOAuth2TokenService()) {
     NTPSnippetsService::RegisterProfilePrefs(pref_service_->registry());
     // Since no SuggestionsService is injected in tests, we need to force the
     // service to fetch from all hosts.
     base::CommandLine::ForCurrentProcess()->AppendSwitch(
         switches::kDontRestrict);
   }
 
-  ~NTPSnippetsServiceTest() override {}
+  ~NTPSnippetsServiceTest() override {
+    if (service_)
+      service_->Shutdown();
+  }
 
   void SetUp() override {
     EXPECT_CALL(mock_scheduler(), Schedule(_, _, _, _)).Times(1);
     CreateSnippetsService(/*enabled=*/true);
   }
 
   void CreateSnippetsService(bool enabled) {
+    if (service_)
+      service_->Shutdown();
+
     scoped_refptr<base::SingleThreadTaskRunner> task_runner(
         base::ThreadTaskRunnerHandle::Get());
     scoped_refptr<net::TestURLRequestContextGetter> request_context_getter =
         new net::TestURLRequestContextGetter(task_runner.get());
 
     service_.reset(new NTPSnippetsService(
         pref_service_.get(), nullptr, task_runner, std::string("fr"),
         &scheduler_,
         base::WrapUnique(new NTPSnippetsFetcher(
             fake_signin_manager_.get(), fake_token_service_.get(),
@@ skipping 224 matching lines @@
   EXPECT_THAT(service()->snippets(), IsEmpty());
   LoadFromJSONString(json_str);
   EXPECT_THAT(service()->snippets(), SizeIs(1));
 }
 
 TEST_F(NTPSnippetsServiceTest, GetDiscarded) {
   LoadFromJSONString(GetTestJson());
 
   // For the test, we need the snippet to get discarded.
   ASSERT_TRUE(service()->DiscardSnippet("http://localhost/foobar"));
-  const NTPSnippetsService::NTPSnippetStorage& snippets =
-      service()->discarded_snippets();
+  const NTPSnippet::PtrVector& snippets = service()->discarded_snippets();
   EXPECT_EQ(1u, snippets.size());
   for (auto& snippet : snippets) {
     EXPECT_EQ("http://localhost/foobar", snippet->id());
   }
 
   // There should be no discarded snippet after clearing the list.
   service()->ClearDiscardedSnippets();
   EXPECT_EQ(0u, service()->discarded_snippets().size());
 }
 
@@ skipping 276 matching lines @@
   EXPECT_THAT(
       tester.GetAllSamples("NewTabPage.Snippets.NumArticlesZeroDueToDiscarded"),
       ElementsAre(base::Bucket(/*min=*/1, /*count=*/1)));
   // Recreating the service and loading from prefs shouldn't count as fetched
   // articles.
   EXPECT_CALL(mock_scheduler(), Schedule(_, _, _, _)).Times(1);
   CreateSnippetsService(/*enabled=*/true);
   tester.ExpectTotalCount("NewTabPage.Snippets.NumArticlesFetched", 4);
 }
 }  // namespace ntp_snippets