[8u40] Review request for RT-38855: DoubleProperty.doubleProperty() Javadoc needs small fix

[Vadim Pakhnushev]

Hi Kevin,

Please review this simple javadoc fix:
https://javafx-jira.kenai.com/browse/RT-38855
http://cr.openjdk.java.net/~vadim/RT-38855/webrev.00/

Thanks,
Vadim