Jim Ferenczi eeac4b9721 Fix Fast Vector Highlighter NPE on match phrase prefix ()
The FVH fails with an NPE when a match phrase prefix is rewritten in an empty phrase query.
This change makes sure that the multi match query rewrites to a MatchNoDocsQuery (instead of an empty phrase query) when there is
a single term and that term does not expand to any term in the index.

Fixes 
2017-06-08 12:27:11 +02:00
..