Filtering with non existing / declared field is ignored

Bug or feature request

• Bug
• Feature request

Description of feature (or steps to reproduce if bug)

1. Insert 10 rows in a model/table
2. Model.find({where: { nonexistingfield: 'test' } })
3. Return 10

Expected result

Return 0 (Memory connector return 0)
Maybe this should return an error ?

Actual result (if bug)

Return all the documents/rows

Additional information (Node.js version, LoopBack version, etc)

Tested with master of loopback-connector-sqlite3

Start by reproducing the issue with the SQLite3 connector using Model.find({where: { nonexistingfield: 'test' } }) after inserting 10 rows. Compare the result with the stated Memory connector behavior and determine whether an unknown field should return zero rows or an error. Done means the SQLite3 connector no longer returns all rows for this filter, with coverage for the reported query.