openlayers/ol3 — pull request #840 by fredj (2013-06-28 09:10:42+00:00)
Title: Add ol.control.Zoom#zoomByDelta function

To replace `ol.control.Zoom#handleIn_` and `ol.control.Zoom#handleOut_` callbacks.

Note that `handleIn_` calls `map.requestRenderFrame()` but not `handleOut_`

Comments welcome.