BindingObserver and BindingSubscriber mustn't use com.sun* classes

[protogenes]

The usage of internal com.sun classes breaks on newer Java versions.

./src/main/java/io/reactivex/rxjavafx/observers/BindingObserver.java
import com.sun.javafx.binding.ExpressionHelper;
./src/main/java/io/reactivex/rxjavafx/observers/BindingSubscriber.java
import com.sun.javafx.binding.ExpressionHelper;

[thomasnield]

Which version(s) is it breaking on? I'm a bit behind and stayed on Java 8, waiting for decoupling to happen with Java 11.

[protogenes]

It is breaking with OpenJDK+OpenJFX 11-ea25
At work we are currently stuck on 8u92 because of changes in later updates that break things. With the upcoming release of version 11 in two weeks I wanted to check what dependencies are missing out and preventing an early update as I want to skip 9 and 10 completely.

[thomasnield]

@protogenes that's my strategy as well. I'll follow up shortly

[thomasnield]

Resolved.