Sample on Jsfiddle: http://jsfiddle.net/rktvybb0/
Related discussion on Stack Overflow: http://stackoverflow.com/questions/27474930/avoid-triggering-overflow-auto-after-resizing-a-child-element-to-matching-size/
Forcing a redraw with a workaround as seen on the following Stack Overflow thread removes the scrollbars: http://stackoverflow.com/a/3485654/1470607
this.offsetHeight; //Won't work without this
While this works as a workaround, it would still be nice to see this fixed.
The problem only occurs when the new dimensions for the child element are given in pixels, when percentage values are used, the issue isn't present.
As of version 63.0.3239.132, this issue is still present.