Fix undefined result in RegExp engine
Fix undefined result in RegExp engine

JerryScript-DCO-1.0-Signed-off-by: Dániel Bátyai dbatyai.u-szeged@partner.samsung.com
JerryScript-DCO-1.0-Signed-off-by: Szilard Ledan szledan.u-szeged@partner.samsung.com

bzsolt/jerryscript,bsdelf/jerryscript,gabrielschulhof/jerryscript,grgustaf/jerryscript,robertsipka/jerryscript,bsdelf/jerryscript,martijnthe/jerryscript,jack60504/jerryscript,glistening/jerryscript,LeeHayun/jerryscript,grgustaf/jerryscript,grgustaf/jerryscript,yichoi/jerryscript,LaszloLango/jerryscript,jerryscript-project/jerryscript,gabrielschulhof/jerryscript,jack60504/jerryscript,yichoi/jerryscript,yichoi/jerryscript,LaszloLango/jerryscript,loki04/jerryscript,jack60504/jerryscript,slaff/jerryscript,tilmannOSG/jerryscript,slaff/jerryscript,jerryscript-project/jerryscript,martijnthe/jerryscript,bsdelf/jerryscript,glistening/jerryscript,zherczeg/jerryscript,jack60504/jerryscript,gabrielschulhof/jerryscript,bzsolt/jerryscript,robertsipka/jerryscript,LaszloLango/jerryscript,slaff/jerryscript,gabrielschulhof/jerryscript,glistening/jerryscript,akosthekiss/jerryscript,jerryscript-project/jerryscript,akosthekiss/jerryscript,bzsolt/jerryscript,loki04/jerryscript,robertsipka/jerryscript,grgustaf/jerryscript,yichoi/jerryscript,dbatyai/jerryscript,robertsipka/jerryscript,LeeHayun/jerryscript,bsdelf/jerryscript,bzsolt/jerryscript,tilmannOSG/jerryscript,martijnthe/jerryscript,akosthekiss/jerryscript,LaszloLango/jerryscript,jack60504/jerryscript,slaff/jerryscript,zherczeg/jerryscript,LeeHayun/jerryscript,tilmannOSG/jerryscript,zherczeg/jerryscript,jack60504/jerryscript,glistening/jerryscript,grgustaf/jerryscript,tilmannOSG/jerryscript,loki04/jerryscript,loki04/jerryscript,loki04/jerryscript,LeeHayun/jerryscript,gabrielschulhof/jerryscript,dbatyai/jerryscript,LaszloLango/jerryscript,glistening/jerryscript,bzsolt/jerryscript,dbatyai/jerryscript,grgustaf/jerryscript,LeeHayun/jerryscript,dbatyai/jerryscript,martijnthe/jerryscript,bsdelf/jerryscript,jerryscript-project/jerryscript,glistening/jerryscript,jerryscript-project/jerryscript,akosthekiss/jerryscript,bsdelf/jerryscript,dbatyai/jerryscript,slaff/jerryscript,martijnthe/jerryscript,yichoi/jerryscript,zherczeg/jerryscript,zherczeg/jerryscript,robertsipka/jerryscript,akosthekiss/jerryscript,tilmannOSG/jerryscript,martijnthe/jerryscript,loki04/jerryscript,robertsipka/jerryscript