Bug 94400 [Undo] - After successful undo, should operation be disposed by framework if it cannot be redone?
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
notifyNotOK(operation);
			throw e;
		} catch (Exception e) {
			notifyNotOK(operation);
			throw new ExecutionException(
					"While executing the operation, an exception occurred", e); 
		}
		
		
		if (!merging) {
			if (status.isOK()) {
				notifyDone(operation);
				
				
				
				
				
				
				
				
				if (operation.canUndo()) {
					add(operation);
				}
			} else {
				notifyNotOK(operation);
			}
		} else {
			
			
			operation.dispose();