android: fix ArrayIndexOutOfBounds on selecting 'Drawings' in DefaultFileFilter setting

Change-Id: I5ed924d9d79db169b11a0561b89da9b57eb078d9
Reviewed-on: https://gerrit.libreoffice.org/66971Reviewed-by: Jan Holesovsky <kendy@collabora.com>
Tested-by: Jan Holesovsky <kendy@collabora.com>

android/source/res/values/arrays.xml

@@ -11,6 +11,7 @@
         <item >0</item>
         <item >1</item>
         <item >2</item>
+        <item >3</item>
     </string-array>
     <string-array name="SupportedLanguagesValues">
         <item >en</item>