Tests compositor basic rAF operation.
Elapsed time: 1000
Requesting first animation frame
Animation frame callback #1
Elapsed time: 1100
Animation frame callback #2
Elapsed time: 1200
Animation frame callback #3
Elapsed time: 1300
Animation frame callback #4
Elapsed time: 1400
Animation frame count: 4

Animation frame callback #5
Screenshot size: 800 x 600
Screenshot rgba: 0,0,50,255