The issue was that Aria allowed too long keys to be created (so that the internal buffer was not big enough to hold the whole key).
Key lengths is now limited to HA_MAX_KEY_LENGTH (1000), as for MyISAM.
Fixed failure in  "_ma_apply_redo_index: Assertion `new_page_length == 0", as found by buildbot.

mysql-test/suite/maria/r/maria.result:
  Updated results
mysql-test/suite/maria/r/maria3.result:
  Updated results. Added test for bug fix
mysql-test/suite/maria/t/maria3.test:
  Updated results. Added test for bug fix
mysql-test/suite/maria/t/optimize.test:
  Updated test for new max key length
storage/maria/ha_maria.cc:
  Limit key to HA_MAX_KEY_LENGTH.
storage/maria/ma_key_recover.c:
  Limit used page length to max page size (this is in line with the code that writes the entry to the log).
  This fixes failure in  "_ma_apply_redo_index: Assertion `new_page_length == 0", as found by buildbot.
storage/maria/ma_search.c:
  Extra DBUG
storage/maria/ma_write.c:
  Added test to detect errors earlier.