Steps to reproduce:
1. Open attached “MenuName.zip” Unity project
2. Open “Test.cs” script in a script editor
3. Change CreateAssetMenu menuName value from “ScriptableTest/test” to “ScriptableTest1/test” and save script
4. Right-click in Project window and open Create submenu


Expected results:
Create menu is updated and old menu item is removed
Actual results:
Both old and new menu items are visible in the Create menu

Reproduced in: 2018.2.0a1, 2018.1.0b8, 2017.3.1p1, 2017.2.1p4, 2017.1.3p1, 2017.1.0a1

Note: The issue is only present in Project window, Assets/Create menu is updated correctly and the old item not visible. Old menu items are removed after reopening or reimporting the project.