[SPARK-12934] use try-with-resources for streams

[tedyu]

@liancheng please take a look

[SparkQA]

Test build #50041 has finished for PR 10906 at commit e400a17.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[zsxwing]

I guess the caller should close the stream?

[tedyu]

Looking at current code, that is not the case.

[zsxwing]

Yeah, it's because only ByteArrayInputStream/ByteArrayOutputStream is used. I think we should document that who should close the stream.

[tedyu]

ERROR: Timeout after 15 minutes
ERROR: Error fetching remote repo 'origin'
hudson.plugins.git.GitException: Failed to fetch from https://github.com/apache/spark.git

[tedyu]

Jenkins, test this please.

[liancheng]

Thanks, LGTM. I'm merging this.

[AmplabJenkins]

Test FAILed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/50059/
Test FAILed.