Do not crash when the user dictionary service is disabled.

This still does not remove the UI. It only prevents the Settings
application from crashing.

Bug: 5024166
Change-Id: I6e8c0a8953af6c02273de2a881e85a5248cb8bd6

src/com/android/settings/inputmethod/UserDictionaryList.java

@@ -49,7 +49,7 @@ public class UserDictionaryList extends SettingsPreferenceFragment {
                 new String[] { UserDictionary.Words.LOCALE },
                 null, null, null);
         final Set<String> localeList = new TreeSet<String>();
-        if (cursor.moveToFirst()) {
+        if (null != cursor && cursor.moveToFirst()) {
             final int columnIndex = cursor.getColumnIndex(UserDictionary.Words.LOCALE);
             do {
                 String locale = cursor.getString(columnIndex);