fix: prevent re-save files (#659)

Author: sdjdd

src/object.js

@@ -1656,6 +1656,8 @@ module.exports = function(AV) {
     var unsavedFiles = [];
     AV.Object._findUnsavedChildren(object, unsavedChildren, unsavedFiles);
 
+    unsavedFiles = _.uniq(unsavedFiles);
+
     var promise = Promise.resolve();
     _.each(unsavedFiles, function(file) {
       promise = promise.then(function() {