Bug 305703 [Viewers][CommonNavigator] remembered contributions can leak when using filters
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/StructuredViewer.java
*            a double-click listener
	 */
	public void removeDoubleClickListener(IDoubleClickListener listener) {
		doubleClickListeners.remove(listener);
	}
	/**
	 * Removes the given filter from this viewer, and triggers refiltering and
	 * resorting of the elements if required. Has no effect if the identical
	 * filter is not registered. If you want to remove more than one filter
	 * consider using {@link StructuredViewer#setFilters(ViewerFilter[])}.
	 * 
	 * @param filter
	 *            a viewer filter
	 * @see StructuredViewer#setFilters(ViewerFilter[])
	 */
	public void removeFilter(ViewerFilter filter) {
		Assert.isNotNull(filter);
		if (filters != null) {
			
			
			for (Iterator i = filters.iterator(); i.hasNext();) {
				Object o = i.next();
				if (o == filter) {
					i.remove();
					refresh();
					if (filters.size() == 0) {
						filters = null;
					}
					return;
				}