Fixed crash caused by File->Quit menu item.
Fixed crash caused by File->Quit menu item.

cedriclaunay/gaffer,johnhaddon/gaffer,hradec/gaffer,johnhaddon/gaffer,chippey/gaffer,lucienfostier/gaffer,chippey/gaffer,boberfly/gaffer,boberfly/gaffer,lucienfostier/gaffer,ivanimanishi/gaffer,goddardl/gaffer,johnhaddon/gaffer,GafferHQ/gaffer,andrewkaufman/gaffer,hradec/gaffer,goddardl/gaffer,cedriclaunay/gaffer,boberfly/gaffer,GafferHQ/gaffer,hradec/gaffer,cedriclaunay/gaffer,GafferHQ/gaffer,lucienfostier/gaffer,andrewkaufman/gaffer,cedriclaunay/gaffer,ImageEngine/gaffer,GafferHQ/gaffer,johnhaddon/gaffer,ImageEngine/gaffer,goddardl/gaffer,ImageEngine/gaffer,ivanimanishi/gaffer,appleseedhq/gaffer,GafferHQ/gaffer,andrewkaufman/gaffer,boberfly/gaffer,appleseedhq/gaffer,ivanimanishi/gaffer,hradec/gaffer,chippey/gaffer,andrewkaufman/gaffer,appleseedhq/gaffer,hradec/gaffer,chippey/gaffer,ivanimanishi/gaffer,goddardl/gaffer,ImageEngine/gaffer,appleseedhq/gaffer,johnhaddon/gaffer,lucienfostier/gaffer,andrewkaufman/gaffer