[Core] Locale dependent code

For me the core tests failed because there are two locale dependent parts in the code.
Look at the Jira ticket for details.

Why is it necessary to check the exception message in isBindCollision in
https://github.com/apache/spark/blob/master/core/src/main/scala/org/apache/spark/util/Utils.scala#L1686
?
I think that's a good fix; just hard-coding `Locale.ENGLISH` is also a fix. On the one hand that's less friendly to the non-English-speaking world, but might avoid some unexpected complications of this form. I expect they will be cosmetic only. I'm indifferent; wonder if anyone else has a though.

BTW you should put the SPARK-XXXX in the title and maybe a more action-oriented title like "Accommodate non-English Locales in unit tests"