Call file->extra() with HA_STATUS_CONST in mysqld_show_keys.
The fix will not be merged into 4.1/5.0 because they don't have this problem already.


mysql-test/r/show_check.result:
  Testcase for BUG#7519
mysql-test/t/show_check.test:
  Testcase for BUG#7519
sql/sql_show.cc:
  Fix for BUG#7519: Index statistics is not displayed after ANALYZE for temporary tables:
  When handling "SHOW INDEX" the call file->extra(HA_STATUS_CONST | ...) is made for regular tables 
  but bypassed for temporary tables. 
  Call file->extra() with HA_STATUS_CONST in mysqld_show_keys to make sure we're always using the 
  current index cardinality values.