Bug 169637 [DataBinding] Multiple validation statuses per binding
bundles/org.eclipse.core.databinding/src/org/eclipse/core/databinding/ListBinding.java
public void handleListChange(ListChangeEvent event) {
			if (!updatingModel) {
				doUpdate((IObservableList) getModel(),
						(IObservableList) getTarget(), event.diff,
						modelToTarget, false, false);
			}
		}
	};
	/**
	 * @param target
	 * @param model
	 * @param modelToTargetStrategy
	 * @param targetToModelStrategy
	 */
	public ListBinding(IObservableList target, IObservableList model,
			UpdateListStrategy targetToModelStrategy,
			UpdateListStrategy modelToTargetStrategy) {
		super(target, model);
		this.targetToModel = targetToModelStrategy;
		this.modelToTarget = modelToTargetStrategy;
		if ((targetToModel.getUpdatePolicy() & UpdateValueStrategy.POLICY_UPDATE) != 0) {
			target.addListChangeListener(targetChangeListener);
		} else {
			targetChangeListener = null;
		}
		if ((modelToTarget.getUpdatePolicy() & UpdateValueStrategy.POLICY_UPDATE) != 0) {
			model.addListChangeListener(modelChangeListener);
		} else {
			modelChangeListener = null;
		}