Fix main screen not realizing account was deleted

Signed-off-by: Daniele Ricci <[email protected]>

Author: daniele-athome

app/src/main/java/org/kontalk/ui/prefs/AccountFragment.java

@@ -362,6 +362,8 @@ public void onClick(@NonNull MaterialDialog dialog, @NonNull DialogAction which)
 
                                 AccountManagerCallback<Boolean> callback = new AccountManagerCallback<Boolean>() {
                                     public void run(AccountManagerFuture<Boolean> future) {
+                                        // invalidate cache
+                                        Kontalk.get().invalidatePersonalKey();
                                         // dismiss progress
                                         progress.dismiss();
                                         // exit now