Is that why it is being reposted? Cause macgap is really old. There are much much better solutions now and days.
(This isn't an area i'm familiar with.)
Chromium Embedded Framework https://code.google.com/p/chromiumembedded/
Atom shell (based on CEF) https://github.com/atom/atom-shell
Brackets Shell (also CEF based) https://github.com/adobe/brackets-shell
node-webkit https://github.com/rogerwang/node-webkit
TideSDK http://www.tidesdk.org/
You can also apparently just roll your own if you want: https://github.com/lostdecade/web_view_example