More G_OBJECT macro fixing.

More G_OBJECT macro fixing.

Original commit message from CVS:
* ext/flac/gstflactag.c:
* gst/alpha/gstalpha.c:
* gst/debug/breakmydata.c:
* gst/debug/negotiation.c:
* gst/debug/testplugin.c:
* gst/effectv/gstaging.c:
* gst/effectv/gstdice.c:
* gst/effectv/gstedge.c:
* gst/effectv/gstquark.c:
* gst/effectv/gstrev.c:
* gst/effectv/gstshagadelic.c:
* gst/effectv/gstvertigo.c:
* gst/effectv/gstwarp.c:
* gst/multipart/multipartdemux.c:
* gst/multipart/multipartmux.c:
* gst/videobox/gstvideobox.c:
* gst/videofilter/gstgamma.c:
* gst/videofilter/gstvideotemplate.c:
* gst/videomixer/videomixer.c:
* sys/sunaudio/gstsunaudiosrc.h:
More G_OBJECT macro fixing.