Populate versions on individual nodes in sync model and native bookmark model.

sync/syncable/directory_backing_store.cc

Index: sync/syncable/directory_backing_store.cc
diff --git a/sync/syncable/directory_backing_store.cc b/sync/syncable/directory_backing_store.cc
index 4f9febf3c4de725cb27aa0268bfa26947916a7f9..ed77464c59dd0a97559611a0a68df8c3f060a0e8 100644
--- a/sync/syncable/directory_backing_store.cc
+++ b/sync/syncable/directory_backing_store.cc
@@ -40,7 +40,7 @@ static const string::size_type kUpdateStatementBufferSize = 2048;
 
 // Increment this version whenever updating DB tables.
 extern const int32 kCurrentDBVersion;  // Global visibility for our unittest.
-const int32 kCurrentDBVersion = 82;
+const int32 kCurrentDBVersion = 83;
 
 // Iterate over the fields of |entry| and bind each to |statement| for
 // updating.  Returns the number of args bound.
@@ -1072,6 +1072,19 @@ bool DirectoryBackingStore::MigrateVersion81To82() {
   return true;
 }
 
+bool DirectoryBackingStore::MigrateVersion82To83() {
+  // Version 83 added transaction_version on sync node.
+  if (!db_->Execute(
+      "ALTER TABLE metas ADD COLUMN transaction_version BIGINT default 0"))
+    return false;
+  sql::Statement update(db_->GetUniqueStatement(
+      "UPDATE metas SET transaction_version = 0"));
+  if (!update.Run())
+    return false;
+  SetVersion(83);
+  return true;
+}
+
 bool DirectoryBackingStore::CreateTables() {
   DVLOG(1) << "First run, creating tables";
   // Create two little tables share_version and share_info