Problem:
In Full-text phrase search, we filter out row that do not contain
all the tokens in the phrase.
If we do not filter out doc_id that doesn't appear in all the
token's doc_id lists then we hit an assert.

Fix:
if any of the token has last doc_id equal to ith doc_id of the first
token doc_id list then filter out rest of the higher doc_ids.

RB: 24909
Reviewed by : Annamalai Gurusami <annamalai.gurusami@oracle.com>

This is a cherry-pick of
mysql/mysql-server@5aa075277dfe84a17a0331c57a6fe9b91dafb4cf
but without a test case, because the test case depends on an n-gram
tokenizer that will be missing from MariaDB until MDEV-10267 is added.