Bug 126839 [DataBinding] IObservable refactoring
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/internal/provisional/databinding/ChangeEvent.java
* @param changeType
	 * @param oldValue
	 * @param newValue
	 * @param position
	 */
	public ChangeEvent(Object source, int changeType, Object oldValue,
			Object newValue, int position) {
		this(source, changeType, oldValue, newValue, null, position);
	}
	
	/**
	 * @param source
	 * @param changeType
	 * @param oldValue
	 * @param newValue
	 * @param parent 
	 * @param position
	 */
	public ChangeEvent(Object source, int changeType, Object oldValue,
			Object newValue, Object parent, int position) {
		super(source);
		this.oldValue = oldValue;
		this.changeType = changeType;
		this.newValue = newValue;
		this.parent = parent;
		this.position = position;		
	}
	/**
	 * Returns the change type (CHANGE, ADD, or REMOVE).
	 *