Require explicit selection of traits for LazyInstance

components/sync/model_impl/model_type_store_backend.cc

 // Copyright 2015 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/model_impl/model_type_store_backend.h"
 
 #include <utility>
 
 #include "base/files/file_path.h"
 #include "base/memory/ptr_util.h"
@@ skipping 14 matching lines @@
 namespace syncer {
 
 const int64_t kInvalidSchemaVersion = -1;
 const int64_t ModelTypeStoreBackend::kLatestSchemaVersion = 1;
 const char ModelTypeStoreBackend::kDBSchemaDescriptorRecordId[] =
     "_mts_schema_descriptor";
 const char ModelTypeStoreBackend::kStoreInitResultHistogramName[] =
     "Sync.ModelTypeStoreInitResult";
 
 // static
-base::LazyInstance<ModelTypeStoreBackend::BackendMap>
+base::LazyInstance<ModelTypeStoreBackend::BackendMap>::DestructorAtExit
     ModelTypeStoreBackend::backend_map_ = LAZY_INSTANCE_INITIALIZER;
 
 namespace {
 
 StoreInitResultForHistogram LevelDbStatusToStoreInitResult(
     const leveldb::Status& status) {
   if (status.ok())
     return STORE_INIT_RESULT_SUCCESS;
   if (status.IsNotFound())
     return STORE_INIT_RESULT_NOT_FOUND;
@@ skipping 211 matching lines @@
 }
 
 // static
 void ModelTypeStoreBackend::RecordStoreInitResultHistogram(
     StoreInitResultForHistogram result) {
   UMA_HISTOGRAM_ENUMERATION(kStoreInitResultHistogramName, result,
                             STORE_INIT_RESULT_COUNT);
 }
 
 }  // namespace syncer