Make sure device pixel ratio is factored into scale <-> resolution conversion
Make sure device pixel ratio is factored into scale <-> resolution conversion

Fixes #1011

jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout,jumpinjackie/mapguide-react-layout