... and remove the debug output of the internal QJsonParseError.
This allows users of the function to get the details in
machine-readable form, and to distinguish between !finished and an
actual Json parsing error.
Found in API-review.
Pick-to: 6.7
Change-Id: Ia237b192a894d692b965f6bedb4c94d3b6537535
Reviewed-by: Juha Vuolle <juha.vuolle@qt.io>