update elements and fix some bugs

lib/src/firebase-element/firebase-document.html

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 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
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@@ skipping 46 matching lines @@
       data: {
         type: Object,
         notify: true
       }
     },
 
     listeners: {
       'firebase-value': '_onFirebaseValue'
     },
 
-    _applyLocalDataChanges: function(change) {
+    _localDataChanged: function(change) {
       var pathFragments = change.path.split('.');
 
       if (pathFragments.length === 1) {
         this._updateRemoteDocument();
         return;
       }
 
       this._setRemoteDocumentChild(
         pathFragments[1],
         change.base[pathFragments[1]]
@@ skipping 13 matching lines @@
 
       return new Firebase(location);
     },
 
     _updateRemoteDocument: function() {
       this._log('Updating remote document');
       this.query.update(this.dataAsObject);
     },
 
     _setRemoteDocumentChild: function(key, value) {
-      this._log('Setting child "' + key + '" to', value);
-      this.query.child(key).set(value);
+      this.debounce('set-' + key, function() {
+        this._log('Setting child "' + key + '" to', value);
+        this.query.child(key).set(value);
+      });
     },
 
     _removeRemoteDocumentChild: function(key) {
       this._log('Removing child "' + key + '"');
       this.query.child(key).remove();
     }
   });
 </script>