Bug 127861 [DataBinding] Mark API provisional
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/updatables/ConvertingSet.java
}
	    			break;
	    			
	    		case ChangeEvent.STALE: 
	    			boolean funcStale = func.isStale();
	    			boolean inputStale = input.isStale();
	    			boolean bothStale = funcStale && inputStale;
	    			boolean noneStale = !funcStale && !inputStale;
	    			
	    			if (noneStale) {
	    				fireStale(false);
	    			} else {
	    				if (!bothStale) {
	    					fireStale(true);
	    				}
	    			}
	    			
	    			break;
	    		default:
    		}
    	}
    };
    
    /**
     * Holds a bi-directional mapping from domain elements onto their values, or null
     * if we are not maintaining a cached result. 
     */
    private InverseMapping converter = null;
    private IUpdatableFunction func;