Original commit message from CVS:
* sys/xvimage/xvimagesink.c: (gst_xvimage_buffer_finalize),
(gst_xvimagesink_xvimage_put), (gst_xvimagesink_setcaps),
(gst_xvimagesink_show_frame), (gst_xvimagesink_buffer_alloc):
* sys/xvimage/xvimagesink.h:
Avoid typechecking when we do trivial casts.
Move error handling out of the main program flow.
Sneak in the display-region caps property, not completely correct yet.
Cache the width/height in buffer_alloc instead of parsing it from the
caps all the time.
e02bde49f2