Webkit border-radius and overflow bug when using any animation/transition

I had the same exact issue. Adding this to the parent container solved it for me (this is a LESS mixin).

.transitionfix() {
    -webkit-backface-visibility: hidden;
    -moz-backface-visibility: hidden;
    -webkit-transform: translate3d(0, 0, 0);
    -moz-transform: translate3d(0, 0, 0)
}

I added minus z-index value for image and higher value for parent

li {z-index:10; overflow: hidden;}

li img {z-index: -10;}