It is an syntax error just as the console said. You miss a )
after the each
function end.
function updateImageSize() {
$(".mr_our-dest-img-container").each(function(){
var ratio_cont = jQuery(this).width()/jQuery(this).height();
var $img = jQuery(this).find("img");
var ratio_img = $img.width()/$img.height();
if (ratio_cont > ratio_img)
{
$img.css({"width": "100%", "height": "auto"});
}
else if (ratio_cont < ratio_img)
{
$img.css({"width": "auto", "height": "100%"});
}
}); //missing )
};