Nyall Dawson c49b5b777f Change a lot of arguments to const references in core/gui
Rationale:
- there was a lot of large objects passed by value, so potentially
there's a speed bump from this
- even for implicitly shared classes like QString/QList there's still
a (small) cost for copying the objects when there's no reason to
- it's the right thing to do!
2015-10-07 12:02:04 +11:00
..