Update TaskTraits in client_cert_store_chromeos.cc.

chrome/browser/chromeos/net/client_cert_store_chromeos.cc

 // Copyright 2013 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 "chrome/browser/chromeos/net/client_cert_store_chromeos.h"
 
 #include <cert.h>
 #include <algorithm>
 #include <utility>
 
@@ skipping 64 matching lines @@
     net::CertificateList* selected_certs,
     const base::Closure& callback,
     const net::CertificateList& additional_certs) {
   std::unique_ptr<crypto::CryptoModuleBlockingPasswordDelegate>
       password_delegate;
   if (!password_delegate_factory_.is_null()) {
     password_delegate.reset(
         password_delegate_factory_.Run(request->host_and_port));
   }
   base::PostTaskWithTraitsAndReply(
-      FROM_HERE,
-      base::TaskTraits().WithWait().WithFileIO().WithShutdownBehavior(
-          base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN),
+      FROM_HERE, base::TaskTraits().MayBlock().WithShutdownBehavior(
+                     base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN),
       base::Bind(&ClientCertStoreChromeOS::GetAndFilterCertsOnWorkerThread,
                  base::Unretained(this), base::Passed(&password_delegate),
                  request, additional_certs, selected_certs),
       callback);
 }
 
 void ClientCertStoreChromeOS::GetAndFilterCertsOnWorkerThread(
     std::unique_ptr<crypto::CryptoModuleBlockingPasswordDelegate>
         password_delegate,
     const net::SSLCertRequestInfo* request,
     const net::CertificateList& additional_certs,
     net::CertificateList* selected_certs) {
   net::CertificateList unfiltered_certs;
   net::ClientCertStoreNSS::GetPlatformCertsOnWorkerThread(
       std::move(password_delegate), &unfiltered_certs);
 
   unfiltered_certs.erase(
       std::remove_if(unfiltered_certs.begin(), unfiltered_certs.end(),
                      CertNotAllowedPredicate(cert_filter_.get())),
       unfiltered_certs.end());
 
   unfiltered_certs.insert(unfiltered_certs.end(), additional_certs.begin(),
                           additional_certs.end());
 
   net::ClientCertStoreNSS::FilterCertsOnWorkerThread(unfiltered_certs, *request,
                                                      selected_certs);
 }
 
 }  // namespace chromeos