Fix possible ArrayOutOfBoundsException in DarculaSpinnerUI.java.

Manifests itself when using Toedter JCalendar library

src/com/bulenkov/darcula/ui/DarculaSpinnerUI.java

@@ -53,10 +53,10 @@ public class DarculaSpinnerUI extends BasicSpinnerUI {
   @Override
   protected void replaceEditor(JComponent oldEditor, JComponent newEditor) {
       super.replaceEditor(oldEditor, newEditor);
-    if (oldEditor != null) {
+      if (oldEditor != null && oldEditor.getComponents().length > 0) {
           oldEditor.getComponents()[0].removeFocusListener(myFocusListener);
       }
-    if (newEditor != null) {
+      if (newEditor != null && newEditor.getComponents().length > 0) {
           newEditor.getComponents()[0].addFocusListener(myFocusListener);
       }
   }