In order to find out the current device scale factor, plug-ins have to use JavaScript to determine the window.devicePixelRatio value. It would be much nicer if we had a simple NPAPI-style API for them to use instead.
<rdar://problem/10048258>
Created attachment 112416 [details] Patch
Committed r98403: <http://trac.webkit.org/changeset/98403>