MIT-licensed postMessage structured clone detection

[#42773699]

https://twitter.com/ryanseddon/status/293205527566110721
Ryan Seddon ‏@ryanseddon
@stephenbannasch sorry meant to do this earlier just created
a gist with MIT license https://gist.github.com/4583494 
7:56 PM - 20 Jan 13 
detect structuredClone, fixes postMessage in IE9

[#42773699]