aggregation function on complex type should give appropriate error

0: jdbc:drill:schema=dfs.drillTestDirComplexJ> select t.soa[1] from `complex.json` t limit 1;
+------------+
|   EXPR$0   |
+------------+
| {"in":1,"fl":1.12345} |
+------------+
1 row selected (0.169 seconds)
0: jdbc:drill:schema=dfs.drillTestDirComplexJ> select avg(t.soa[1]) from `complex.json` t;
+--+
|  |
+--+
+--+
No rows selected (0.164 seconds)