Bug 252117 [DataBinding] ListBinding does not update from model to target in some cases
bundles/org.eclipse.core.databinding.beans/src/org/eclipse/core/internal/databinding/beans/JavaBeanObservableSet.java
try {
			Set removals = new HashSet();
			for (Iterator iterator = wrappedSet.iterator(); iterator.hasNext();) {
				Object element = iterator.next();
				if (!c.contains(element)) {
					iterator.remove();
					removals.add(element);
				}
			}
			boolean changed = !removals.isEmpty();
			if (changed) {
				setValues();
				fireSetChange(Diffs.createSetDiff(Collections.EMPTY_SET,
						removals));
			}
			return changed;
		} finally {
			updating = false;
		}
	}
	public void clear() {
		getterCalled();
		if (wrappedSet.isEmpty())
			return;
		updating = true;
		try {
			Set removals = new HashSet(wrappedSet);
			wrappedSet.clear();
			setValues();
			fireSetChange(Diffs.createSetDiff(Collections.EMPTY_SET, removals));