test-journal: use new _add_frame_callback api
test-journal: use new _add_frame_callback api

This updates test-journal to use the new
cogl_onscreen_add_frame_callback() api to use _SYNC events for
throttling.

(cherry picked from commit 24e6a5376ed3982f5647e2c2df0618272c381636)

Distrotech/cogl,Distrotech/cogl,Distrotech/cogl,Distrotech/cogl