Revert "Add support for lyrics."

id3v2metadata.go

@@ -37,7 +37,6 @@ var frames = frameNames(map[string][2]string{
 	"disc":         [2]string{"TPA", "TPOS"},
 	"genre":        [2]string{"TCO", "TCON"},
 	"picture":      [2]string{"PIC", "APIC"},
-	"lyrics":       [2]string{"", "USLT"},
 })
 
 // metadataID3v2 is the implementation of Metadata used for ID3v2 tags.
@@ -113,14 +112,6 @@ func (m metadataID3v2) Disc() (int, int) {
 	return parseXofN(m.getString(frames.Name("disc", m.Format())))
 }
 
-func (m metadataID3v2) Lyrics() string {
-	t, ok := m.frames[frames.Name("lyrics", m.Format())]
-	if !ok {
-		return ""
-	}
-	return t.(*Comm).Text
-}
-
 func (m metadataID3v2) Picture() *Picture {
 	v, ok := m.frames[frames.Name("picture", m.Format())]
 	if !ok {