fix potential miscalculation of growth duration
fix potential miscalculation of growth duration

davidgoli/liquid-fire,ember-animation/ember-animated,ef4/liquid-fire,ember-animation/ember-animated,csantero/liquid-fire,ember-animation/ember-animated,ianstarz/liquid-fire,jayphelps/liquid-fire,ef4/liquid-fire,dsokolowski/liquid-fire,givanse/liquid-fire,twokul/liquid-fire,twokul/liquid-fire,jamesreggio/liquid-fire,ember-animation/liquid-fire-core,envoy/liquid-fire,jayphelps/liquid-fire,byelipk/liquid-fire,byelipk/liquid-fire,monegraph/liquid-fire,knownasilya/liquid-fire,ember-animation/liquid-fire-velocity,monegraph/liquid-fire,mikegrassotti/liquid-fire,ianstarz/liquid-fire,acorncom/liquid-fire,jrjohnson/liquid-fire,givanse/liquid-fire,ember-animation/liquid-fire-core,ember-animation/liquid-fire,acorncom/liquid-fire,runspired/liquid-fire,dsokolowski/liquid-fire,gordonbisnor/liquid-fire,chadhietala/liquid-fire,chadhietala/liquid-fire,mikegrassotti/liquid-fire,ember-animation/liquid-fire-velocity,jrjohnson/liquid-fire,jamesreggio/liquid-fire,ember-animation/liquid-fire,davidgoli/liquid-fire,gordonbisnor/liquid-fire,csantero/liquid-fire,runspired/liquid-fire,knownasilya/liquid-fire