fix CallEvent::popIndex calculation
fix CallEvent::popIndex calculation

badlogic/avian,getlantern/avian,MaartenR/avian,badlogic/avian,getlantern/avian,getlantern/avian,marcinolawski/avian,lwahlmeier/avian,marcinolawski/avian,lwahlmeier/avian,bgould/avian,lwahlmeier/avian,minor-jason/avian,lostdj/avian,minor-jason/avian,ucdseniordesign/avian,bgould/avian,lwahlmeier/avian,marcinolawski/avian,bigfatbrowncat/avian-pack.avian,dicej/avian,joshuawarner32/avian,bgould/avian,joshuawarner32/avian,lostdj/avian,joshuawarner32/avian,dicej/avian,dicej/avian,bigfatbrowncat/avian-pack.avian,dicej/avian,joshuawarner32/avian,ucdseniordesign/avian,lostdj/avian,ucdseniordesign/avian,lostdj/avian,MaartenR/avian,getlantern/avian,ucdseniordesign/avian,badlogic/avian,minor-jason/avian,bigfatbrowncat/avian-pack.avian,bigfatbrowncat/avian-pack.avian,minor-jason/avian,bgould/avian,marcinolawski/avian,badlogic/avian,MaartenR/avian,MaartenR/avian