Retina Display Support

Any chance of adding Retina support to Window Resizer? Currently on Retina displays, resizing to a particular resolution, say 640x1136, will result in a browser window effectively resized to 1280x2272 (exactly double). 

Obviously this makes testing for specific resolutions difficult. Customizing particular resolution to be half of their initial value only gets you so far since it appears that the Chrome browser does not allow windows to be resized below a width of 400px. Emulating iPhone screens, which have a width of 320 in real pixels is therefore not possible