While the class name is now a bit more than a mouthful, it's purpose
is very narrowly tied to QTextDocument, so don't use a very generic
name for it. That resources are provided based on a URL is to some
degree an implementation detail, and URLs are resource locators so
we don't need that in the class name.
Address code review comment for 6.1. Add documentation and links to
existing APIs with a similar purpose.
Task-number: QTBUG-90211
Task-number: QTBUG-92208
Pick-to: 6.1
Change-Id: I4f09057cc2f53a5595513c1c9422e6ccaad6ca13
Reviewed-by: Kai Koehne <kai.koehne@qt.io>
c8f6f8a222