Bug 123316 [Undo] - API BEHAVIOR - should always place a successfully undone/redone op on the redo/undo history
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
if (operation.canUndo()) {
					add(operation);
				} else {
					
					
					
					
					operation.dispose();
				}
			} else {
				notifyNotOK(operation, status);
				
				
				operation.dispose();
			}
		}
		
		return status;
	}
	/*
	 * Filter the specified list to include only the specified undo context.
	 */
	private IUndoableOperation[] filter(List list, IUndoContext context) {
		/*
		 * This method is used whenever there is a need to filter the undo or
		 * redo history on a particular context. Currently there are no caches
		 * kept to optimize repeated requests for the same filter. If benchmarks
		 * show this to be a common pattern that causes performances problems,