extendscript-es5-shim/Object/getPrototypeOf.js

a collection of useful es5-shims for Extendscript

if (!Object.getPrototypeOf) {
	Object.getPrototypeOf = function(object) {
		if (Object(object) !== object) {
			throw new TypeError('Object.getPrototypeOf can only be called on Objects.');
		}
		return object.__proto__;
	}
}