StandaloneFileBrowser.SaveFilePanelAsync does use directory as defaultName

[NoxMortem]

StandaloneFileBrowser.SaveFilePanelAsync(title,directory,defaultName) does actually open a filebrowser on windows with directory as defaultName in some random folder (likely the last saved position?)

In StandaloneFileBrowserWindows.SaveFilePanel

			if (!string.IsNullOrEmpty(directory))
			{
				finalFilename = GetDirectoryPath(directory);
			}

Should be

			if (!string.IsNullOrEmpty(directory))
			{
				finalFilename = GetDirectoryPath(directory);
		          	if (Directory.Exists(finalFilename))
					fd.InitialDirectory = finalFilename;
			}