[chronojump] Fix on preferences/open logs folder

[Xavier de Blas <xaviblas src gnome org>]

commit 9ba08d97e610456d8c0c311dc18be2fc23928802
Author: Xavier de Blas <xaviblas gmail com>
Date:   Sun May 31 11:24:26 2020 +0200

    Fix on preferences/open logs folder

 src/gui/preferences.cs | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)
---
diff --git a/src/gui/preferences.cs b/src/gui/preferences.cs
index 6385bff6..aabb6840 100644
--- a/src/gui/preferences.cs
+++ b/src/gui/preferences.cs
@@ -1439,17 +1439,19 @@ public class PreferencesWindow
        void on_button_tmp_folder_open_clicked (object o, EventArgs args)
        {
                string dir = UtilAll.GetTempDir(); //potser cal una arrobar abans (a windows)
-               System.IO.FileInfo fInfo = new System.IO.FileInfo(dir);
+
+               if( ! new System.IO.DirectoryInfo(dir).Exists)
+               {
+                       LogB.Warning(dir);
+                       return;
+               }
 
                try {
-                       if(fInfo.Exists)
-                               System.Diagnostics.Process.Start(dir);
+                       System.Diagnostics.Process.Start(dir);
                } catch {
                        new DialogMessage(Constants.MessageTypes.WARNING, 
                                        Constants.DirectoryCannotOpenStr() + "\n\n" + dir);
                }
-
-               LogB.Warning(dir);
        }
 
        void on_button_import_configuration_clicked (object o, EventArgs args)