Merge pull request #195 from UnityTech/yczhang

Fix RefreshIndicator.

Runtime/material/refresh_indicator.cs

                             return;
                         }
 
-                        refreshResult.Then(() => {
+                        refreshResult.Finally(() => {
                             if (this.mounted && this._mode == _RefreshIndicatorMode.refresh) {
                                 completer.Resolve();
                                 this._dismiss(_RefreshIndicatorMode.done);