Globals clobbering other globals

[ryanseddon]

So I've been playing around with building a simple markdown component and that component uses showdown.js now I've started noticing weird behaviour where the callstack would randomly jump into showdown.js and it's due to the fact that both libraries have a forEach global where showdown wins as it's loaded after. It's defined in the lang.js file.

Does it really need to be a global? Showdown is global crazy but it'd be nice if polymer didn't create any globals.

[sjmiles]

There shouldn't be any globals apart from one for each polyfill, but there is still some cleanup work to do.

[tjsavage]

This should be fixed, please re-open if that's not the case.