[SPARK-9748] [MLlib] Centriod typo in KMeansModel

[BertrandDechoux]

A minor typo (centriod -> centroid). Readable variable names help every users.

[jkbradley]

ok to test

[jkbradley]

LGTM pending tests.
@BertrandDechoux Could you please create a JIRA and link the JIRA number in the title? We're trying to do that even for small PRs.

[BertrandDechoux]

Sure. The documentation should be updated then.

https://cwiki.apache.org/confluence/display/SPARK/Contributing+to+Spark

However, trivial changes, where the what should change is virtually the same as the how it should change do not require a JIRA. Example: "Fix typos in Foo scaladoc"

[srowen]

Yeah, this seems below the level of a JIRA to me. Describing it is almost the same as fixing it. I am not sure we're trying to make every single change a JIRA. In any event it's easier to just make a JIRA than debate it in this instance.

[mengxr]

Agree with @srowen . It should be okay to mark this PR title as [MINOR].

[jkbradley]

Oh OK I thought we were discouraging the use of minor, but that's fine with me

[SparkQA]

Test build #1406 has finished for PR 8037 at commit 47632fe.

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

[jkbradley]

Merging with master. Thanks!