Advanced Search should not search email for text entered into "Name" field

If the "includeEmail" option is enabled, the advanced search form will incorrectly generate a query which also searches email for text entered into "name".

I'm not sure if it yields incorrect result rows.

This is a problem for us because the generated query is inefficient (5 minutes to run one query).

The name/email search is actually a problem on its own. I've worked around it with a UNION query which works much better. It shouldn't be too hard to modify contact search to use this sort of construct: https://gerrit.wikimedia.org/r/gitweb?p=wikimedia/fundraising/crm.git;a=blob;f=sites/all/modules/wmf_common/wmf_civicrm/wmf_civicrm.module;h=f2221991f900b1a814b31fb80d1e7e1c83f47500;hb=0701e95e9f0ea5dd1574e1e1dfe5335a54a979e4#l1333