Removed 5.15 specific QVector code, which is unlikely usable now when
we are at 6.1+ timeline (that was really only a nice-to-have during
5.15 -> 6.0 transition)
Added "remove first" benchmark to track the fast (or not so fast)
removal path
Updated mid insertion and mid emplace to actually trigger both paths
(growing at the beginning and at the end), before it was really using
just one side, which is not quite the "mid" way it feels. Also changed
mid insertion to actually use the insert algorithm. Seems like
insert(i, t) calls emplace under the hood at least from the visual
introspection
Change-Id: I01b82cfa0ae38d481ea7362947f3607d757bf5d0
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
3edba4b3d5