sync: Move migration signal out of snapshot

sync/internal_api/public/sessions/model_neutral_state.h

 // Copyright 2012 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.
 
 #ifndef SYNC_SESSIONS_MODEL_NEUTRAL_STATE_H
 #define SYNC_SESSIONS_MODEL_NEUTRAL_STATE_H
 
 #include "base/basictypes.h"
 #include "sync/base/sync_export.h"
 #include "sync/internal_api/public/base/model_type.h"
@@ skipping 17 matching lines @@
   int num_successful_commits;
 
   // This is needed for monitoring extensions activity.
   int num_successful_bookmark_commits;
 
   // Download event counters.
   int num_updates_downloaded_total;
   int num_tombstone_updates_downloaded_total;
   int num_reflected_updates_downloaded_total;
 
-  // If the syncer encountered a MIGRATION_DONE code, these are the types that
-  // the client must now "migrate", by purging and re-downloading all updates.
-  ModelTypeSet types_needing_local_migration;
-
   // Update application and conflicts.
   int num_updates_applied;
   int num_encryption_conflicts;
   int num_server_conflicts;
   int num_hierarchy_conflicts;
 
   // Overwrites due to conflict resolution counters.
   int num_local_overwrites;
   int num_server_overwrites;
 
@@ skipping 11 matching lines @@
   // really is nothing more to download.
   int64 num_server_changes_remaining;
 };
 
 bool HasSyncerError(const ModelNeutralState& state);
 
 }  // namespace sessions
 }  // namespace syncer
 
 #endif  // SYNC_SESSIONS_MODEL_NEUTRAL_STATE_H_