Function: x-dnd-handle-moz-url

Handle one item of type text/x-moz-url.
WINDOW is the window where the drop happened. ACTION is ignored.
DATA is the moz-url, which is formatted as two strings separated by \r\n.
The first string is the URL, the second string is the title of that URL.
DATA is encoded in utf-16. Decode the URL and call `x-dnd-handle-uri-list'.