Fixd for 5490443 Native crash while exporting a video

- Add new onError callback to PreviewProgressListener, which is
used to indicate video editor application for the error that has occurred during
priviewing.
With this modification, the application must implement the onError method,
and then VideoEditorPreviewTest.java is changed accordingly.

Change-Id: I15610b8907fcf8bd35a3c69ad7c07b5175a6e309