Crash when trying to open root directory

[ozonexo3]

UnityStandaloneFileBrowser/Assets/StandaloneFileBrowser/StandaloneFileBrowserWindows.cs

Line 129 in def85a6

return Path.GetDirectoryName(directoryPath) + Path.DirectorySeparatorChar;

It crash for "C://" directory. We can add that before to fix it:

			if (System.IO.Path.GetPathRoot(directoryPath) == directoryPath)
				return directoryPath;