[9] Code Review Request 8163385: Fix doclint errors and warnings in javafx.controls module

[Chien Yang]

Hi Jonathan and Kevin,

Please review the proposed fix.

JIRA: https://bugs.openjdk.java.net/browse/JDK-8163385

Webrev: http://cr.openjdk.java.net/~ckyang/JDK-8163385/webrev.00/

Thanks,

- Chien