This changes all the containers that uses QtPrivate::RefCount
(QMap already had one), and QVariant
In Qt 4.8, it was pointless to have the move constructor because we did
not have quick way to re-initialize a null container. (shared_null still
needed to be refcounted)
But now that we have RefCount, and that the shared_null do not have
reference count, we can implement a fast move constructor that do not generate
code to increment the reference count.
Change-Id: I2bc3c6ae96983f08aa7b1c7cb98d44a89255160b
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@nokia.com>
f92fdd190d