For QMap on a std::pair, QMap::iterator{}.operator->() would result in a
type that has "first" and "second" members: std::pair itself. But it
would be wrong to marshall and demarshall the first and second elements
thereof as the key and value, so give preference to the .key() and
.value() selection, which would store the std::pair as the type.
Fixes: QTBUG-123401
Pick-to: 6.5 6.6 6.7
Change-Id: I6818d78a57394e37857bfffd17bd69bb692dd03b
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
5401a9a6cd