base: Remove the string logging from CHECK().

components/sync/engine_impl/loopback_server/persistent_unique_client_entity.cc

 // Copyright 2014 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/sync/engine_impl/loopback_server/persistent_unique_client_entity.h"
 
 #include <stdint.h>
 
 #include <memory>
 #include <string>
@@ skipping 22 matching lines @@
       creation_time_(creation_time),
       last_modified_time_(last_modified_time) {
   SetSpecifics(specifics);
 }
 
 PersistentUniqueClientEntity::~PersistentUniqueClientEntity() {}
 
 // static
 std::unique_ptr<LoopbackServerEntity> PersistentUniqueClientEntity::Create(
     const sync_pb::SyncEntity& client_entity) {
-  CHECK(client_entity.has_client_defined_unique_tag())
-      << "A PersistentUniqueClientEntity must have a client-defined unique "
-         "tag.";
+  // A PersistentUniqueClientEntity must have a client-defined unique tag.
+  CHECK(client_entity.has_client_defined_unique_tag());
   ModelType model_type = GetModelTypeFromSpecifics(client_entity.specifics());
   string id = EffectiveIdForClientTaggedEntity(client_entity);
   return std::unique_ptr<LoopbackServerEntity>(new PersistentUniqueClientEntity(
       id, model_type, client_entity.version(), client_entity.name(),
       client_entity.client_defined_unique_tag(), client_entity.specifics(),
       client_entity.ctime(), client_entity.mtime()));
 }
 
 // static
 std::string PersistentUniqueClientEntity::EffectiveIdForClientTaggedEntity(
@@ skipping 21 matching lines @@
 void PersistentUniqueClientEntity::SerializeAsProto(
     sync_pb::SyncEntity* proto) const {
   LoopbackServerEntity::SerializeBaseProtoFields(proto);
 
   proto->set_client_defined_unique_tag(client_defined_unique_tag_);
   proto->set_ctime(creation_time_);
   proto->set_mtime(last_modified_time_);
 }
 
 }  // namespace syncer