[SPARK-17075][SQL] Follow up: fix file line ending and improve the tests

## What changes were proposed in this pull request?

Fixed the line ending of `FilterEstimation.scala` (It's still using `\n\r`). Also improved the tests to cover the cases where the literals are on the left side of a binary operator.

## How was this patch tested?

Existing unit tests.

Author: Shuai Lin <linshuai2012@gmail.com>

Closes #17051 from lins05/fix-cbo-filter-file-encoding.