QML url type automatically performs some URL decoding

Assigning a string containing URL-encoded characters (e.g. %25) to a QML property of type url automatically converts some of these to their decoded characters.

This is bad if a webserver expects, for example, the actual "%25" instead of "/".

Qt.resolvedUrl() also changes some of those characters.

Code examples:

  // contains the original string
  property string origUrlStr: "https://test.com/a%20b%2fc%25d"

  // contains "https://test.com/a b/c%25d"
  property url origUrl: origUrlStr

  // contains https://test.com/a b%2fc%25d
  property string resolvedUrlStr: Qt.resolvedUrl(origUrlStr)

  // contains https://test.com/a b/c%25d
  property url resolvedUrl: Qt.resolvedUrl(origUrlStr)

As a result, it is impossible to use this URL as the source of a QML Image:
https://firebasestorage.googleapis.com/v0/b/vplaytest-9b010.appspot.com/o/images%2Fvplay-logo.png?alt=media&token=482900ca-e65e-4df2-8df3-cfade271ec8b

Because the "%2F" is changed to "/" and the server then returns status 400:
https://firebasestorage.googleapis.com/v0/b/vplaytest-9b010.appspot.com/o/images/vplay-logo.png?alt=media&token=482900ca-e65e-4df2-8df3-cfade271ec8b