CQL searching for intersections of users and content has unexpected results

Issue Summary

/api/search and the /api/content/search both return unexpected results when searching for intersections of type=user and type=content

Steps to Reproduce

1. Make a CQL search for an intersection of user and content types.

Expected Results

• type = page AND type = user returns all pages.

• type = page OR type = user returns all pages.

• type IN (page,user) returns all pages.

• type != page AND type = user, this returns all content types except pages. Content types include page, blog, attachment, comment.

Actual Results

Examples:

• type = page AND type = user returns all the pages. This is the expected behavior.  The same goes for any other combination with user (blogpost+user, space+user, and user+page, user+blogpost, user+space), these ignore the user filter. 

• type = page OR type = user returns only all the users, instead of all users+pages. Same for any other combination, these all return the users and ignore the other filter.

• type IN (page,user) returns only all the users, instead of all users+pages. Same for any other combination, these all return the users and ignore the other filter.

• type != page AND type = user, this returns an unexpected number of results, except when the user is at the front (ex.: type != user AND type = page), which all work correctly.

This is reproducible on Data Center: no

Workaround

• Break CQL queries into separate subqueries on type=user or type=content.
• Use /wiki/api/content/search REST API for content search. This API doesn't return users.