Avoid a disk write on UI thread

bug: 2983837
Change-Id: I4eca20fb4defcf149788032a98fe5894b57e1e19

java/src/com/android/inputmethod/latin/LanguageSwitcher.java

@@ -188,7 +188,7 @@ public class LanguageSwitcher {
         SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(mIme);
         Editor editor = sp.edit();
         editor.putString(LatinIME.PREF_INPUT_LANGUAGE, getInputLanguage());
-        editor.commit();
+        editor.apply();
     }
 
     static String toTitleCase(String s) {