added resolution initialization for osx backend
added resolution initialization for osx backend

It's important step of initialization because all features calls from font rendering libs based on this parameter. By default it equals to -1 and test-text-cache test  crashes in this case.

rkudiyarov/clutter_osx,rkudiyarov/clutter_osx,rkudiyarov/clutter_osx,rkudiyarov/clutter_osx