Fix bug while setting default language

The previous change which introduced the new way options were handled
introduced a bug, which is fixed by this change.

Bug: translateselectedtext:11
Change-Id: I268031e7bd504d1529ab824eb6fdeb1ee71fbdf6
diff --git a/src/common/options.js b/src/common/options.js
index bfe668b..8861881 100644
--- a/src/common/options.js
+++ b/src/common/options.js
@@ -83,9 +83,9 @@
             let defaultLang2 = uiLocale.split('_')[0];
 
             items.translateinto = {};
-            if (isoLangs[default_language_1] != undefined)
+            if (isoLangs[defaultLang1] != undefined)
               items.translateinto['0'] = defaultLang1;
-            else if (isoLangs[default_language_2] != undefined)
+            else if (isoLangs[defaultLang2] != undefined)
               items.translateinto['0'] = defaultLang2;
           }
         }