Fix possible panic on short slices

Author: Jacalz

src/mime/type_unix.go

@@ -43,7 +43,9 @@ func loadMimeGlobsFile(filename string) error {
 	for scanner.Scan() {
 		// Each line should be of format: weight:mimetype:*.ext
 		fields := strings.Split(scanner.Text(), ":")
-		if len(fields) < 2 || fields[0][0] == '#' || fields[2][0] != '*' {
+		if len(fields) < 3 || len(fields[0]) < 1 || len(fields[2]) < 2 {
+			continue
+		} else if fields[0][0] == '#' || fields[2][0] != '*' {
 			continue
 		}