Print icon causes fatal error when clicked on transaction related pages (Event Registration and Online Contribution Pages)

We blow the session off at the end, and hence cannot redisplay the page Thank You page in printer friendly view (this causes a fatal error for the print icon).

We've modified the behavior of the print icon for online contribution and event registration pages so it just calls javascript window.print function rather than trying to load our special "printer friendly" version of the page. This should be sufficient to allow users to print the thank you page with pay-later instructions and/or other "receipt" info.