[PATCH] emacs: set query-context to nil if its "" or "*"

[David Bremner]

Jani Nikula <jani at nikula.org> writes:
> Notmuch show and tree buffers inadvertently combine the thread query
> with said special queries, causing incorrect collapsing of
> messages. Handle the special queries specially. We already do a
> similar thing in notmuch-search-filter.

pushed

d