Bug 127861 [DataBinding] Mark API provisional
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/updatables/ConvertingSet.java
Object target = converter.getValue(next);
			
			if (target != null) {
				Collection keys = converter.removeMapping(next);
				
				
				if (keys.isEmpty()) {
					removes.add(target);
				}
			}
		}
        fireRemoved(removes);
    }
    
    protected void processChanges(Collection collection) {
    	
    	
    	Assert.isNotNull(converter, "The identity function should never fire a change event"); 
    	
    	processRemoves(collection);
    	processAdds(collection);
	}
	public Object getAdapter(Object element) {
		
		if (func == IdentityFunction.getInstance()) {
			return element;
		}