Remove editControlsContainer param, return constructed editor
Remove editControlsContainer param, return constructed editor

- Unregister event listener on owned control close

larsbrubaker/MatterControl,unlimitedbacon/MatterControl,mmoening/MatterControl,jlewin/MatterControl,jlewin/MatterControl,larsbrubaker/MatterControl,jlewin/MatterControl,larsbrubaker/MatterControl,unlimitedbacon/MatterControl,unlimitedbacon/MatterControl,larsbrubaker/MatterControl,jlewin/MatterControl,unlimitedbacon/MatterControl,mmoening/MatterControl,mmoening/MatterControl