Fix QUrl handling after QUrl changes.

toString() is fine for most usages but here the result is made part of XML
bits, so toEncoded() is necessary so that '<' and '>' are percent-encoded.

Change-Id: I41832cefe3ae12cab13531f17095d0804a2e86d9
Sanity-Review: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>