Bug 305703 [Viewers][CommonNavigator] remembered contributions can leak when using filters
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/StructuredViewer.java
} else {
				Widget[] widgets = (Widget[]) widgetOrWidgets;
				int indexOfItem = Arrays.asList(widgets).indexOf(item);
				if (indexOfItem == -1) {
					int length = widgets.length;
					System.arraycopy(widgets, 0,
							widgets = new Widget[length + 1], 0, length);
					widgets[length] = item;
					elementMap.put(element, widgets);
				}
			}
		}
	}
	/**
	 * Determines whether a change to the given property of the given element
	 * would require refiltering and/or resorting.
	 * <p>
	 * This method is internal to the framework; subclassers should not call
	 * this method.
	 * </p>
	 * 
	 * @param element
	 *            the element
	 * @param property
	 *            the property
	 * @return <code>true</code> if refiltering is required, and
	 *         <code>false</code> otherwise
	 */
	protected boolean needsRefilter(Object element, String property) {
		if (sorter != null && sorter.isSorterProperty(element, property)) {