Inspired by the AppIcon Gnome Goal, I worked on using the icon theme for various application icons in gnome-media.  I also somewhat zealously cleaned up icons that didn't seem to be used anymore.  Let me know if I went too far.

Notes:
* Removed <icons>...</icons> from gnome-cd themes (was only in None theme).  Looks like this is old support for theming of UI widgets, but has since been replaced by proper theming.  It wasn't even being parsed by the XML parser.  I removed this XML chunk from the .theme and removed the icons.

* Got rid of gnome-mixer.png in favor of standard icon "multimedia-volume-control"

* gnome-grecord.png lives in both gnome-media and gnome-icon-theme.  I suspect it should just live in gnome-media, but I don't know policy on that kind of thing.

* gst-mixer and gnome-cd still use custom images (gst-mixer for an assortment of widget icons, see bug 310883; gnome-cd for its themes, see bug 353238).

* gstreamer-properties.png isn't namespaced well.  Shouldn't we use gnome-gstreamer-properties.png instead?

* The following files can be deleted:
 grecord/pixmaps/
 grecord/pixmaps/gnome_mixer.xpm
 gst-mixer/pixmaps/gnome-mixer.png
 gnome-cd/images/media/media-fwd.png
 gnome-cd/images/media/media-stop.png
 gnome-cd/images/media/a-stop-menu.png
 gnome-cd/images/media/media-eject.png
 gnome-cd/images/media/a-first-menu.png
 gnome-cd/images/media/a-eject-menu.png
 gnome-cd/images/media/media-rew.png
 gnome-cd/images/media/media-play.png
 gnome-cd/images/media/a-last-menu.png
 gnome-cd/images/media/a-play-menu.png
 gnome-cd/images/media/media-rec.png
 gnome-cd/images/media/media-prev.png
 gnome-cd/images/media/media-pause.png
 gnome-cd/images/media/media-next.png
 gnome-cd/images/media-eject.png
 gnome-cd/images/None/media-fwd.png
 gnome-cd/images/None/media-stop.png
 gnome-cd/images/None/a-stop-menu.png
 gnome-cd/images/None/a-first-menu.png
 gnome-cd/images/None/media-eject.png
 gnome-cd/images/None/media-rew.png
 gnome-cd/images/None/a-eject-menu.png
 gnome-cd/images/None/media-play.png
 gnome-cd/images/None/a-last-menu.png
 gnome-cd/images/None/a-play-menu.png
 gnome-cd/images/None/media-prev.png
 gnome-cd/images/None/media-pause.png
 gnome-cd/images/None/media-next.png
 gnome-cd/images/lcd/a-fwd.png
 gnome-cd/images/lcd/a-pause-pressed.png
 gnome-cd/images/lcd/a-fwd-pressed.png
 gnome-cd/images/lcd/a-first.png
 gnome-cd/images/lcd/a-first-menu.png
 gnome-cd/images/lcd/a-eject.png
 gnome-cd/images/lcd/a-first-pressed.png
 gnome-cd/images/lcd/a-eject-pressed.png
 gnome-cd/images/lcd/a-rwnd.png
 gnome-cd/images/lcd/a-rwnd-pressed.png
 gnome-cd/images/lcd/a-stop.png
 gnome-cd/images/lcd/a-stop-menu.png
 gnome-cd/images/lcd/a-stop-pressed.png
 gnome-cd/images/lcd/a-eject-menu.png
 gnome-cd/images/lcd/a-last.png
 gnome-cd/images/lcd/a-last-menu.png
 gnome-cd/images/lcd/a-play.png
 gnome-cd/images/lcd/a-last-pressed.png
 gnome-cd/images/lcd/a-play-menu.png
 gnome-cd/images/lcd/a-play-pressed.png
 gnome-cd/images/lcd/a-pause.png
 gnome-cd/images/mixer.png
 gnome-cd/images/a-play-menu.png
 gnome-cd/images/cd.png
 gnome-cd/images/red-lcd/a-fwd.png
 gnome-cd/images/red-lcd/a-pause-pressed.png
 gnome-cd/images/red-lcd/a-fwd-pressed.png
 gnome-cd/images/red-lcd/a-first.png
 gnome-cd/images/red-lcd/a-first-menu.png
 gnome-cd/images/red-lcd/a-eject.png
 gnome-cd/images/red-lcd/a-first-pressed.png
 gnome-cd/images/red-lcd/a-eject-pressed.png
 gnome-cd/images/red-lcd/a-rwnd.png
 gnome-cd/images/red-lcd/a-rwnd-pressed.png
 gnome-cd/images/red-lcd/a-stop.png
 gnome-cd/images/red-lcd/a-stop-menu.png
 gnome-cd/images/red-lcd/a-stop-pressed.png
 gnome-cd/images/red-lcd/a-eject-menu.png
 gnome-cd/images/red-lcd/a-last.png
 gnome-cd/images/red-lcd/a-last-menu.png
 gnome-cd/images/red-lcd/a-play.png
 gnome-cd/images/red-lcd/a-last-pressed.png
 gnome-cd/images/red-lcd/a-play-menu.png
 gnome-cd/images/red-lcd/a-play-pressed.png
 gnome-cd/images/red-lcd/a-pause.png

(I have SVN access to do the above if approved.)