[test-cogl-tex-tile] Fix breakages from ClutterFixed removal and timelines

[test-cogl-tex-tile] Fix breakages from ClutterFixed removal and timelines

The test has been broken since the change to use floats instead of
fixed point because it was passing degrees to sin and cos but they
expect radians.

It was further broken since the timeline changes because it was
directly using the parameter of the new-frame signal as a frame number
but it now represents the elapsed time.