metadata.c was not in the POTFILES.in.
./src/cache.c
./src/cache_maint.c
./src/cellrenderericon.c
-./src/collect.c
./src/collect-dlg.c
./src/collect-io.c
./src/collect-table.c
+./src/collect.c
./src/desktop_file.c
./src/dupe.c
./src/editors.c
-./src/exif.c
./src/exif-common.c
+./src/exif.c
./src/filedata.c
./src/fullscreen.c
./src/histogram.c
./src/history_list.c
-./src/image.c
./src/image-overlay.c
+./src/image.c
./src/img-view.c
./src/layout.c
./src/layout_config.c
./src/logwindow.c
./src/main.c
./src/menu.c
+./src/metadata.c
./src/options.c
./src/pan-view.c
./src/preferences.c