[SPARK-13423][HOTFIX] Static analysis fixes for 2.x / fixed for Scala 2.10

## What changes were proposed in this pull request?

Fixes compile problem due to inadvertent use of `Option.contains`, only in Scala 2.11. The change should have been to replace `Option.exists(_ == x)` with `== Some(x)`. Replacing exists with contains only makes sense for collections. Replacing use of `Option.exists` still makes sense though as it's misleading.

## How was this patch tested?

Jenkins tests / compilation

(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)

Author: Sean Owen <sowen@cloudera.com>

Closes #11493 from srowen/SPARK-13423.2.