...where the previous .uno:PrintPreview request has not yet been processed, the
same way it had been made more robust for ScAccessiblePageHeader.java in
5b5c52a3 "Try make this more robust in slow
environments" plus b5dd2b42 "Also cope with
intermittend DisposedExceptions."

Change-Id: I64389b817d91a2bed8dfe1b8d92bafec42eba21a