hg: openjfx/11-dev/rt: 8222788: javafx.web build fails on XCode 10.2

[johan at lodgon.com]

Changeset: e600b55c9d74
Author:    arajkumar
Date:      2019-05-17 14:59 +0530
URL:       https://hg.openjdk.java.net/openjfx/11-dev/rt/rev/e600b55c9d74

8222788: javafx.web build fails on XCode 10.2
Reviewed-by: kcr, jvos

! modules/javafx.web/src/main/native/Source/WTF/wtf/Optional.h