[Sync] Ensure that CONFIGURE_CLEAN types get unapplied before configuration

components/sync/driver/glue/sync_backend_host_impl.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 "components/sync/driver/glue/sync_backend_host_impl.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 266 matching lines @@
   // non-nigori type in the request requires migration, a MIGRATION_DONE
   // response will be sent.
 
   ModelSafeRoutingInfo routing_info;
   registrar_->GetModelSafeRoutingInfo(&routing_info);
 
   ModelTypeSet current_types = registrar_->GetLastConfiguredTypes();
   ModelTypeSet types_to_purge = Difference(ModelTypeSet::All(), current_types);
   ModelTypeSet inactive_types =
       GetDataTypesInState(CONFIGURE_INACTIVE, config_state_map);
+  // Include clean_first_types in types_to_purge, they are part of
+  // current_types, but still need to be cleared.
+  DCHECK(current_types.HasAll(clean_first_types));
+  types_to_purge.PutAll(clean_first_types);
   types_to_purge.RemoveAll(inactive_types);
   types_to_purge.RemoveAll(unready_types);
 
   // If a type has already been disabled and unapplied or journaled, it will
   // not be part of the |types_to_purge| set, and therefore does not need
   // to be acted on again.
   fatal_types.RetainAll(types_to_purge);
   ModelTypeSet unapply_types = Union(crypto_types, clean_first_types);
   unapply_types.RetainAll(types_to_purge);
 
@@ skipping 398 matching lines @@
     const SyncManager::ClearServerDataCallback& frontend_callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
   frontend_callback.Run();
 }
 
 }  // namespace syncer
 
 #undef SDVLOG
 
 #undef SLOG