Pref service: enable for user prefs in chrome behind a flag.

services/preferences/public/cpp/persistent_pref_store_client.cc

 // Copyright 2017 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 "services/preferences/public/cpp/persistent_pref_store_client.h"
 
 #include <utility>
 
 #include "base/values.h"
 #include "components/prefs/pref_registry.h"
+#include "mojo/public/cpp/bindings/sync_call_restrictions.h"
 #include "services/preferences/public/cpp/pref_registry_serializer.h"
 
 namespace prefs {
 
 PersistentPrefStoreClient::PersistentPrefStoreClient(
     mojom::PrefStoreConnectorPtr connector,
     scoped_refptr<PrefRegistry> pref_registry)
     : connector_(std::move(connector)),
       pref_registry_(std::move(pref_registry)) {
   DCHECK(connector_);
@@ skipping 54 matching lines @@
 PersistentPrefStore::PrefReadError PersistentPrefStoreClient::GetReadError()
     const {
   return read_error_;
 }
 
 PersistentPrefStore::PrefReadError PersistentPrefStoreClient::ReadPrefs() {
   mojom::PersistentPrefStoreConnectionPtr connection;
   std::unordered_map<PrefValueStore::PrefStoreType,
                      prefs::mojom::PrefStoreConnectionPtr>
       other_pref_stores;
+  mojo::SyncCallRestrictions::ScopedAllowSyncCall allow_sync_calls;
   if (!connector_->Connect(SerializePrefRegistry(*pref_registry_), &connection,
                            &other_pref_stores)) {
     NOTREACHED();
   }
   pref_registry_ = nullptr;
   OnConnect(std::move(connection), std::move(other_pref_stores));
   return read_error_;
 }
 
 void PersistentPrefStoreClient::ReadPrefsAsync(
@@ skipping 42 matching lines @@
 
   if (connection->pref_store_connection) {
     Init(std::move(connection->pref_store_connection->initial_prefs), true,
          std::move(connection->pref_store_connection->observer));
   } else {
     Init(nullptr, false, nullptr);
   }
 }
 
 }  // namespace prefs