autoanalyze failed when a table has global index, analyze version = 1

[L-maple]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

set global tidb_analyze_version = 1;
use test;
CREATE TABLE t ( a int, b int, c int default 0)
  PARTITION BY RANGE (a) (
  PARTITION p0 VALUES LESS THAN (10),
  PARTITION p1 VALUES LESS THAN (20),
  PARTITION p2 VALUES LESS THAN (30),
  PARTITION p3 VALUES LESS THAN (40));
INSERT INTO t(a, b) values(1, 1), (2, 2), (3, 3), (15, 15), (25, 25), (35, 35);
ALTER TABLE t ADD UNIQUE INDEX idx(b);
set global tidb_partition_prune_mode = "dynamic";

2. What did you expect to see? (Required)

auto analyze run successfully.

3. What did you see instead (Required)

auto analyze run failed, global index should be handle specifically.

4. What is your TiDB version? (Required)