use of eval() in dimension-handler.js requires undesirable CSP script-src 'unsafe-eval'

[jptrainor]

The dimension-handler.js code uses eval(). Is there anyway other it can be implemented? It prevents use of script-src 'unsafe-eval' as part of a Content-Security-Policy.

I found this in a polymer application that is deployed in an iOS WKWebView. The paper-drop-down menu animates something using this polyfill and it breaks badly due to the eval() failing as a result of an 'unsafe-eval' policy setting. It's a shame to have to remove 'unsafe-eval' just for sake of animation. I'd be okay with a slower animation if that's the trade off.