upload: re-add upload by bytes

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/BackupActivity.java

@@ -39,6 +39,7 @@ public class BackupActivity extends BaseActivity {
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
+        // noinspection ConstantConditions, we know this activity has an action bar
         getSupportActionBar().setDisplayHomeAsUpEnabled(true);
 
         if (savedInstanceState == null) {