PDF macro breaks on pages with a colon in the title

Steps to reproduce:

1. Create a page with a colon (":") in the title and attach PDF documents.
2. Go to insert a PDF macro.

Instead of the drop-down containing a list of PDF documents attached to the page, it will be empty.

The AJAX call to /json/attachmentsearch.action will fail with a 404 because it is using bad spaceKey and title parameters. The colon seems to confuse whatever is trying to extract them.