SPATIAL key is fine actually, but the chk_key() function
mistakenly returns error. It tries to compare checksums
of btree and SPATIAL keys while the checksum for the SPATIAL isn't
calculated (always 0). Same thing with FULLTEXT keys is handled
using full_text_keys counter, so fixed by counting both
SPATIAL and FULLTEXT keys in that counter.


myisam/mi_check.c:
  Bug #30284 spatial key corruption
  
  full_text_keys counts both FULL_TEXT and SPATIAL keys
mysql-test/r/gis.result:
  Bug #30284 spatial key corruption
  
  test result
mysql-test/t/gis.test:
  Bug #30284 spatial key corruption.
  
  test case