In the QSparqlResult::hasError() and lastError() methods, only return a valid result if isFinished is true.
In the QSparqlResult::hasError() and lastError() methods, only return a valid result if isFinished is true.

A patch from Richard Dale.

vranki/libqtsparql,vranki/libqtsparql,vranki/libqtsparql,vranki/libqtsparql