Description of problem:

Performing search queries that contain single quotes ('), generates invalid SQL.  This appears to be an issue in the scoped_search gem.

This was observed using the scoped_search auto-complete feature.  The auto-complete suggested the following as a search query; however, submitting that query generates an exception:

description  =  "Association named 'user' was not found; perhaps you misspelled it?"

Note: auto-complete should only suggest queries that are 'valid'.

Version-Release number of selected component (if applicable):
master

How reproducible:
always

Steps to Reproduce:
1. perform a search query that contains single quotes.  E.g. description = "this is an 'invalid' query"
2.
3.
  
Actual results:
Exception.  Using the example from the description generates an error like:

SQLite3::SQLException: near "user": syntax error: SELECT DISTINCT "notices".text FROM "notices" INNER JOIN "user_notices" ON "notices"."id" = "user_notices"."notice_id" INNER JOIN "users" ON "users"."id" = "user_notices"."user_id" WHERE "users"."id" = 3 AND (text LIKE 'Association named 'user' was not found; perhaps you misspelled it?%') LIMIT 20


Expected results:

Valid search results returned.

Additional info: