Part 2:
Searching fulltext index for a word with boolean mode truncation
operator may cause infinite loop.

The problem was that "smarter index merge" was used with "trunc-words",
which must never happen.

Affects 5.1 only.


mysql-test/r/fulltext.result:
  Addition to a test case for BUG#29445.
mysql-test/t/fulltext.test:
  Addition to a test case for BUG#29445.
storage/myisam/ft_boolean_search.c:
  Fulltext "smarter index merge" optimization assumes that rows
  it gets are ordered by doc_id. That is not the case when we
  search for a word with truncation operator. It may return
  rows in random order. Thus we may not use "smarter index merge"
  optimization with "trunc-words".
  
  Also fixed compiler warning introduced by Part 1 patch.