remove 'return'

[y-shimizu]

looks unnecessary 😀

[srowen]

Although it's unnecessary, I think this kind of thing is generally too trivial to bother opening a PR for by itself.

[AmplabJenkins]

Can one of the admins verify this patch?

[mengxr]

Agree. But since we have a PR already, let's call Jenkins:)

ok to test

[mengxr]

test this please

[SparkQA]

Test build #26333 has started for PR 4268 at commit 12be0e9.

• This patch merges cleanly.

[SparkQA]

Test build #26333 has finished for PR 4268 at commit 12be0e9.

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

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/26333/
Test PASSed.