Use TaskScheduler instead of WorkerPool in nss_cert_database.cc.

chrome/browser/chromeos/policy/policy_cert_verifier_browsertest.cc

Index: chrome/browser/chromeos/policy/policy_cert_verifier_browsertest.cc
diff --git a/chrome/browser/chromeos/policy/policy_cert_verifier_browsertest.cc b/chrome/browser/chromeos/policy/policy_cert_verifier_browsertest.cc
index 13763da61e682afb13e05ea331ce202b348601b4..0db6131d2d23b4a0444e3fd2273fa1c62743c9a8 100644
--- a/chrome/browser/chromeos/policy/policy_cert_verifier_browsertest.cc
+++ b/chrome/browser/chromeos/policy/policy_cert_verifier_browsertest.cc
@@ -45,8 +45,6 @@ class PolicyCertVerifierTest : public testing::Test {
         crypto::GetPrivateSlotForChromeOSUser(
             test_nss_user_.username_hash(),
             base::Callback<void(crypto::ScopedPK11Slot)>())));
-    test_cert_db_->SetSlowTaskRunnerForTest(
-        base::ThreadTaskRunnerHandle::Get());
 
     cert_verifier_.reset(new PolicyCertVerifier(base::Bind(
         &PolicyCertVerifierTest::OnTrustAnchorUsed, base::Unretained(this))));