Update LayerMixin.js

Author: Ryan Haywood

lib/LayerMixin.js

@@ -53,6 +53,7 @@ var LayerMixin = {
  layer.alpha = style.alpha;
  layer.backgroundColor = style.backgroundColor;
  layer.borderColor = style.borderColor;
+ layer.borderWidth = style.borderWidth;
  layer.borderRadius = style.borderRadius;
  layer.clipRect = style.clipRect;
  layer.frame = FrameUtils.make(style.left || 0, style.top || 0, style.width || 0, style.height || 0);