Ryo Munakata authored Aug 10, 2014 and Pekka Paalanen committed Aug 18, 2014

At the calculation of the first FPS, gears has initialized last
FPS time with gettimeofday().
But the callback_data passed in the callback of wl_surface_frame()
is the current time, in milliseconds, with an undefined base.
Because of this subtracting last FPS time from callback_data makes no sense.
 For example, below is the result of running weston-gears on weston with
drm backend:

$ weston-gears
Warning: FPS count is limited by the wayland compositor or monitor refresh rate
1 frames in 1094460.125 seconds =  0.000 FPS
301 frames in  5.016 seconds = 60.008 FPS
301 frames in  5.016 seconds = 60.008 FPS
301 frames in  5.016 seconds = 60.008 FPS

As you can see, the the first FPS value is something odd.

This patch fixes it by initializing last FPS time with the callback_data passed in
the first callback.

Reviewed-by: Nils Chr. Brause <nilschrbrause@gmail.com>