krazy fix: use QStringRef::isEmpty() instead of comparing with "".
krazy fix: use QStringRef::isEmpty() instead of comparing with "".

svn path=/trunk/KDE/kdeedu/marble/; revision=1033164

adraghici/marble,rku/marble,tucnak/marble,probonopd/marble,adraghici/marble,Earthwings/marble,tzapzoor/marble,utkuaydin/marble,quannt24/marble,tucnak/marble,Earthwings/marble,oberluz/marble,oberluz/marble,David-Gil/marble-dev,oberluz/marble,adraghici/marble,David-Gil/marble-dev,David-Gil/marble-dev,utkuaydin/marble,probonopd/marble,rku/marble,probonopd/marble,tzapzoor/marble,rku/marble,AndreiDuma/marble,David-Gil/marble-dev,David-Gil/marble-dev,utkuaydin/marble,probonopd/marble,utkuaydin/marble,AndreiDuma/marble,adraghici/marble,Earthwings/marble,Earthwings/marble,tzapzoor/marble,quannt24/marble,quannt24/marble,rku/marble,probonopd/marble,adraghici/marble,tzapzoor/marble,adraghici/marble,tzapzoor/marble,probonopd/marble,oberluz/marble,tzapzoor/marble,tucnak/marble,quannt24/marble,tucnak/marble,Earthwings/marble,oberluz/marble,AndreiDuma/marble,AndreiDuma/marble,quannt24/marble,rku/marble,utkuaydin/marble,tzapzoor/marble,AndreiDuma/marble,AndreiDuma/marble,David-Gil/marble-dev,rku/marble,quannt24/marble,tucnak/marble,Earthwings/marble,tucnak/marble,tzapzoor/marble,probonopd/marble,oberluz/marble,utkuaydin/marble,quannt24/marble,tucnak/marble