[Sync] Add support for sync Persistence Errors

chrome/browser/sync/glue/bookmark_model_associator.h

 // Copyright (c) 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 CHROME_BROWSER_SYNC_GLUE_BOOKMARK_MODEL_ASSOCIATOR_H_
 #define CHROME_BROWSER_SYNC_GLUE_BOOKMARK_MODEL_ASSOCIATOR_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 123 matching lines @@
   bool AssociateTaggedPermanentNode(
       const BookmarkNode* permanent_node,
       const std::string& tag) WARN_UNUSED_RESULT;
 
   // Compare the properties of a pair of nodes from either domain.
   bool NodesMatch(const BookmarkNode* bookmark,
                   const syncer::BaseNode* sync_node) const;
 
   // Check whether bookmark model and sync model are synced by comparing
   // their transaction versions.
-  void CheckModelSyncState(syncer::SyncMergeResult* local_merge_result,
-                           syncer::SyncMergeResult* syncer_merge_result) const;
+  // Returns a PERSISTENCE_ERROR if a transaction mismatch was detected where
+  // the native model has a newer transaction verison.
+  syncer::SyncError CheckModelSyncState(
+      syncer::SyncMergeResult* local_merge_result,
+      syncer::SyncMergeResult* syncer_merge_result) const;
 
   BookmarkModel* bookmark_model_;
   Profile* profile_;
   syncer::UserShare* user_share_;
   DataTypeErrorHandler* unrecoverable_error_handler_;
   const bool expect_mobile_bookmarks_folder_;
   BookmarkIdToSyncIdMap id_map_;
   SyncIdToBookmarkNodeMap id_map_inverse_;
   // Stores sync ids for dirty associations.
   DirtyAssociationsSyncIds dirty_associations_sync_ids_;
 
   // Used to post PersistAssociation tasks to the current message loop and
   // guarantees no invocations can occur if |this| has been deleted. (This
   // allows this class to be non-refcounted).
   base::WeakPtrFactory<BookmarkModelAssociator> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BookmarkModelAssociator);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_GLUE_BOOKMARK_MODEL_ASSOCIATOR_H_