Bug 166052 [Viewers] Regression: decorator of DecoratingLabelProvider completely replaces label provider
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/DecoratingLabelProvider.java
Assert.isNotNull(provider);
		this.provider = provider;
		this.decorator = decorator;
	}
	/**
	 * The <code>DecoratingLabelProvider</code> implementation of this
	 * <code>IBaseLabelProvider</code> method adds the listener to both the
	 * nested label provider and the label decorator.
	 * 
	 * @param listener
	 *            a label provider listener
	 */
	public void addListener(ILabelProviderListener listener) {
		super.addListener(listener);
		provider.addListener(listener);
		if (decorator != null) {
			decorator.addListener(listener);
		}
		listeners.add(listener);
	}
	/**
	 * The <code>DecoratingLabelProvider</code> implementation of this
	 * <code>IBaseLabelProvider</code> method disposes both the nested label
	 * provider and the label decorator.
	 */
	public void dispose() {
		provider.dispose();
		if (decorator != null) {
			decorator.dispose();
		}