cgen: fix type_default for option type when the default expr is none
#13063
| Job | Run time |
|---|---|
| 2m 6s | |
| 1m 52s | |
| 41s | |
| 4m 39s |
none
#13063
| Job | Run time |
|---|---|
| 2m 6s | |
| 1m 52s | |
| 41s | |
| 4m 39s |