Revert "Fix CertVerifierService initialization in some unittests"

This reverts commit a79726df.

Reason for revert: This is suspected to break some network-related tests

Original change's description:
> Fix CertVerifierService initialization in some unittests
>
> The manual resetting of the CertVerifierServiceFactory in between
> unit_tests seems not to work on Android. So, refactor the
> initialization code to look like the Storage Service's, using
> SequenceLocalStorage to reset the CertVerifierServiceFactory
> between unit tests.
>
> Bug: 1015134, 1094483
> Change-Id: Ic13f67274cecd49450279da401fb4cd29c9b1e94
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2520377
> Reviewed-by: John Abd-El-Malek <jam@chromium.org>
> Commit-Queue: Matthew Denton <mpdenton@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#825141}

TBR=jam@chromium.org,mpdenton@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1015134, 1094483, 1146899
Change-Id: I4903c4c8fa157f0e47cefd32cfb679fe144d050e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2524812
Commit-Queue: Rakina Zata Amni <rakina@chromium.org>
Reviewed-by: Rakina Zata Amni <rakina@chromium.org>
Cr-Commit-Position: refs/heads/master@{#825251}

content/browser/network_service_instance_impl.cc

@@ -520,22 +520,12 @@ GetNewCertVerifierServiceRemote(
   return cert_verifier_remote;
 }
 
-void RunInProcessCertVerifierServiceFactory(
+void CreateInProcessCertVerifierServiceOnThread(
     mojo::PendingReceiver<cert_verifier::mojom::CertVerifierServiceFactory>
         receiver) {
-#if defined(OS_CHROMEOS)
-  DCHECK(!BrowserThread::IsThreadInitialized(BrowserThread::IO) ||
-         BrowserThread::CurrentlyOn(BrowserThread::IO));
-#else
-  DCHECK(!BrowserThread::IsThreadInitialized(BrowserThread::UI) ||
-         BrowserThread::CurrentlyOn(BrowserThread::UI));
-#endif
-  static base::NoDestructor<base::SequenceLocalStorageSlot<
-      std::unique_ptr<cert_verifier::CertVerifierServiceFactoryImpl>>>
-      service_factory_slot;
-  service_factory_slot->GetOrCreateValue() =
-      std::make_unique<cert_verifier::CertVerifierServiceFactoryImpl>(
-          std::move(receiver));
+  // Except in tests, our CertVerifierServiceFactoryImpl is a singleton.
+  static base::NoDestructor<cert_verifier::CertVerifierServiceFactoryImpl>
+      cv_service_factory(std::move(receiver));
 }
 
 // Owns the CertVerifierServiceFactory used by the browser.
@@ -543,19 +533,16 @@ void RunInProcessCertVerifierServiceFactory(
 class CertVerifierServiceFactoryOwner {
  public:
   CertVerifierServiceFactoryOwner() = default;
-
   CertVerifierServiceFactoryOwner(const CertVerifierServiceFactoryOwner&) =
       delete;
   CertVerifierServiceFactoryOwner& operator=(
       const CertVerifierServiceFactoryOwner&) = delete;
-
-  ~CertVerifierServiceFactoryOwner() = default;
+  ~CertVerifierServiceFactoryOwner() = delete;
 
   static CertVerifierServiceFactoryOwner* Get() {
-    static base::NoDestructor<
-        base::SequenceLocalStorageSlot<CertVerifierServiceFactoryOwner>>
+    static base::NoDestructor<CertVerifierServiceFactoryOwner>
         cert_verifier_service_factory_owner;
-    return &cert_verifier_service_factory_owner->GetOrCreateValue();
+    return &*cert_verifier_service_factory_owner;
   }
 
   // Passing nullptr will reset the current remote.
@@ -578,10 +565,10 @@ class CertVerifierServiceFactoryOwner {
       // See for example InitializeNSSForChromeOSUser().
       GetIOThreadTaskRunner({})->PostTask(
           FROM_HERE,
-          base::BindOnce(&RunInProcessCertVerifierServiceFactory,
+          base::BindOnce(&CreateInProcessCertVerifierServiceOnThread,
                          service_factory_remote_.BindNewPipeAndPassReceiver()));
 #else
-      RunInProcessCertVerifierServiceFactory(
+      CreateInProcessCertVerifierServiceOnThread(
           service_factory_remote_.BindNewPipeAndPassReceiver());
 #endif
       service_factory_ = service_factory_remote_.get();

content/public/test/unittest_test_suite.cc

@@ -56,6 +56,21 @@ class ResetNetworkServiceBetweenTests : public testing::EmptyTestEventListener {
   DISALLOW_COPY_AND_ASSIGN(ResetNetworkServiceBetweenTests);
 };
 
+// Similarly to the above, the global CertVerifierServiceFactory object needs
+// to be destructed in between tests.
+class ResetCertVerifierServiceFactoryBetweenTests
+    : public testing::EmptyTestEventListener {
+ public:
+  ResetCertVerifierServiceFactoryBetweenTests() = default;
+
+  void OnTestEnd(const testing::TestInfo& test_info) override {
+    SetCertVerifierServiceFactoryForTesting(nullptr);
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ResetCertVerifierServiceFactoryBetweenTests);
+};
+
 }  // namespace
 
 UnitTestTestSuite::UnitTestTestSuite(base::TestSuite* test_suite)
@@ -72,6 +87,7 @@ UnitTestTestSuite::UnitTestTestSuite(base::TestSuite* test_suite)
   testing::TestEventListeners& listeners =
       testing::UnitTest::GetInstance()->listeners();
   listeners.Append(new ResetNetworkServiceBetweenTests);
+  listeners.Append(new ResetCertVerifierServiceFactoryBetweenTests);
 
   // The ThreadPool created by the test launcher is never destroyed.
   // Similarly, the FeatureList created here is never destroyed so it