PrettyPageHandler: clarify return type for getDataTables
PrettyPageHandler: clarify return type for getDataTables

emilkje/whoops,nonconforme/whoops,michabbb-backup/whoops,michabbb-backup/whoops,staabm/whoops,oligriffiths/whoops,emilkje/whoops,staabm/whoops,UnderDogg/whoops,Vmak11/whoops,filp/whoops,Vmak11/whoops,stefen/whoops,stefen/whoops,nonconforme/whoops,filp/whoops,UnderDogg/whoops,oligriffiths/whoops