Minor fix to dynamic cast introduced in e4edd69
Minor fix to dynamic cast introduced in e4edd69

In case of a NanoAOD, fHeader is casted to the wrong type in
AliAODEvent::GetHeader.  The dynamic cast could then fail: we need to
recast to TObject before that.

sebaleh/AliRoot,alisw/AliRoot,miranov25/AliRoot,mkrzewic/AliRoot,coppedis/AliRoot,alisw/AliRoot,mkrzewic/AliRoot,miranov25/AliRoot,mkrzewic/AliRoot,miranov25/AliRoot,coppedis/AliRoot,mkrzewic/AliRoot,ecalvovi/AliRoot,jgrosseo/AliRoot,sebaleh/AliRoot,sebaleh/AliRoot,ALICEHLT/AliRoot,miranov25/AliRoot,ecalvovi/AliRoot,ALICEHLT/AliRoot,jgrosseo/AliRoot,sebaleh/AliRoot,ALICEHLT/AliRoot,miranov25/AliRoot,alisw/AliRoot,coppedis/AliRoot,ALICEHLT/AliRoot,mkrzewic/AliRoot,shahor02/AliRoot,sebaleh/AliRoot,jgrosseo/AliRoot,miranov25/AliRoot,ALICEHLT/AliRoot,jgrosseo/AliRoot,shahor02/AliRoot,shahor02/AliRoot,ecalvovi/AliRoot,shahor02/AliRoot,ecalvovi/AliRoot,alisw/AliRoot,miranov25/AliRoot,alisw/AliRoot,coppedis/AliRoot,ecalvovi/AliRoot,alisw/AliRoot,jgrosseo/AliRoot,coppedis/AliRoot,shahor02/AliRoot,coppedis/AliRoot,miranov25/AliRoot,mkrzewic/AliRoot,coppedis/AliRoot,coppedis/AliRoot,ALICEHLT/AliRoot,ecalvovi/AliRoot,shahor02/AliRoot,alisw/AliRoot,sebaleh/AliRoot,alisw/AliRoot,sebaleh/AliRoot,ALICEHLT/AliRoot,jgrosseo/AliRoot,mkrzewic/AliRoot,shahor02/AliRoot,jgrosseo/AliRoot,ecalvovi/AliRoot