Refactor the ecma_string_substr function (#1517)
Refactor the ecma_string_substr function (#1517)

JerryScript-DCO-1.0-Signed-off-by: Robert Sipka rsipka.uszeged@partner.samsung.com
gabrielschulhof/jerryscript,slaff/jerryscript,zherczeg/jerryscript,gabrielschulhof/jerryscript,martijnthe/jerryscript,martijnthe/jerryscript,akosthekiss/jerryscript,dbatyai/jerryscript,glistening/jerryscript,glistening/jerryscript,grgustaf/jerryscript,jack60504/jerryscript,LaszloLango/jerryscript,martijnthe/jerryscript,bsdelf/jerryscript,bsdelf/jerryscript,akosthekiss/jerryscript,bsdelf/jerryscript,yichoi/jerryscript,yichoi/jerryscript,robertsipka/jerryscript,slaff/jerryscript,bzsolt/jerryscript,zherczeg/jerryscript,glistening/jerryscript,yichoi/jerryscript,grgustaf/jerryscript,loki04/jerryscript,slaff/jerryscript,dbatyai/jerryscript,robertsipka/jerryscript,jack60504/jerryscript,grgustaf/jerryscript,bsdelf/jerryscript,bsdelf/jerryscript,jerryscript-project/jerryscript,martijnthe/jerryscript,jack60504/jerryscript,loki04/jerryscript,jerryscript-project/jerryscript,dbatyai/jerryscript,loki04/jerryscript,loki04/jerryscript,gabrielschulhof/jerryscript,robertsipka/jerryscript,bzsolt/jerryscript,dbatyai/jerryscript,dbatyai/jerryscript,glistening/jerryscript,glistening/jerryscript,jerryscript-project/jerryscript,bsdelf/jerryscript,akosthekiss/jerryscript,zherczeg/jerryscript,gabrielschulhof/jerryscript,LaszloLango/jerryscript,LaszloLango/jerryscript,zherczeg/jerryscript,yichoi/jerryscript,zherczeg/jerryscript,martijnthe/jerryscript,bzsolt/jerryscript,yichoi/jerryscript,bzsolt/jerryscript,jack60504/jerryscript,martijnthe/jerryscript,grgustaf/jerryscript,jack60504/jerryscript,robertsipka/jerryscript,slaff/jerryscript,akosthekiss/jerryscript,LaszloLango/jerryscript,jerryscript-project/jerryscript,slaff/jerryscript,robertsipka/jerryscript,grgustaf/jerryscript,loki04/jerryscript,jerryscript-project/jerryscript,akosthekiss/jerryscript,robertsipka/jerryscript,grgustaf/jerryscript,bzsolt/jerryscript,glistening/jerryscript,gabrielschulhof/jerryscript,loki04/jerryscript,jack60504/jerryscript,LaszloLango/jerryscript