Change of default behavior of When

[Nir Lisker]

Hi all,

The class javafx.beans.binding.When is using eager evaluation of its
arguments [1]. Kevin and I discussed the idea of changing this default
behavior to the more intuitive lazy evaluation as done in a simple ternary
expression. This is a potentially breaking change for current code that
(for some reason) relies on both values being evaluated regardless of the
condition's value. This behavior is not documented.

If anyone has any reservations, please voice them over the next few days.

Thanks,
Nir

[1] https://bugs.openjdk.java.net/browse/JDK-8089579