Unity bug workaround "in timestamps but is not known in assetdatabase"

ReimportUnityEngineUI.cs

using UnityEngine;
using System.Collections.Generic;
using UnityEditor;
using System.Text.RegularExpressions;
using System.IO;
using System.Text;
 
 
// http://forum.unity3d.com/threads/unityengine-ui-dll-is-in-timestamps-but-is-not-known-in-assetdatabase.274492/#post-1942214
public class ReimportUnityEngineUI
{
    [MenuItem( "Assets/Reimport UI Assemblies", false, 100 )]
    public static void ReimportUI()
    {
#if UNITY_4_6
        var path = EditorApplication.applicationContentsPath + "/UnityExtensions/Unity/GUISystem/{0}/{1}";
        var version = Regex.Match( Application.unityVersion,@"^[0-9]+\.[0-9]+\.[0-9]+").Value;
#else
        var path = EditorApplication.applicationContentsPath + "/UnityExtensions/Unity/GUISystem/{1}";
        var version = string.Empty;
#endif
        string engineDll = string.Format( path, version, "UnityEngine.UI.dll");
        string editorDll = string.Format( path, version, "Editor/UnityEditor.UI.dll");
        ReimportDll( engineDll );
        ReimportDll( editorDll );
               
    }
    static void ReimportDll(string path )
    {
        if ( File.Exists( path ) )
            AssetDatabase.ImportAsset( path, ImportAssetOptions.ForceUpdate| ImportAssetOptions.DontDownloadFromCacheServer );
        else
            Debug.LogError( string.Format( "DLL not found {0}", path ) );
    }
}