SPA_AUDIO_LAYOUT_(MONO|STEREO)

In spa/include/spa/param/audio/layout.h, SPA_AUDIO_LAYOUT_MPEG_1_0 and SPA_AUDIO_LAYOUT_MPEG_2_0 are defined to SPA_AUDIO_LAYOUT_MONO and SPA_AUDIO_LAYOUT_STEREO, respectively. But these values are themselves not defined.

Are actually SPA_AUDIO_LAYOUT_Mono and SPA_AUDIO_LAYOUT_Stereo meant, which are available further up in the file?