[Sync] Move model_type* from syncable/ to base/

sync/internal_api/public/engine/model_safe_worker.cc

Index: sync/internal_api/public/engine/model_safe_worker.cc
diff --git a/sync/internal_api/public/engine/model_safe_worker.cc b/sync/internal_api/public/engine/model_safe_worker.cc
index 0bde89b8be6e64fef8ceb8ec1ed81ad68b2d327a..f3722d40632d7bcbd9d2c8b42cf5b21738e54ef2 100644
--- a/sync/internal_api/public/engine/model_safe_worker.cc
+++ b/sync/internal_api/public/engine/model_safe_worker.cc
@@ -29,6 +29,17 @@ std::string ModelSafeRoutingInfoToString(
   return json;
 }
 
+syncable::ModelTypePayloadMap ModelSafeRoutingInfoToPayloadMap(
+    const ModelSafeRoutingInfo& routes,
+    const std::string& payload) {
+  syncable::ModelTypePayloadMap types_with_payloads;
+  for (ModelSafeRoutingInfo::const_iterator i = routes.begin();
+       i != routes.end(); ++i) {
+    types_with_payloads[i->first] = payload;
+  }
+  return types_with_payloads;
+}
+
 syncable::ModelTypeSet GetRoutingInfoTypes(
     const ModelSafeRoutingInfo& routing_info) {
   syncable::ModelTypeSet types;