Wrong input box filled with multiple file fields

[roidayan]

Just noticed this but the example shows a bug where there are multi tabs and each tab has a file field.
The first file field you use is working.
Now choose different tab and choose image for the file field there and it's input field is not being filled. Instead the url being filled in the first file field you used in the other tab.

[roidayan]

this is because when we first create the file frame we set a callback which text field to fill.
on later calls if file frame exists we don't override this.

                if ( file_frame ) {
                    file_frame.open();
                    return false;
                }

.........

                file_frame.on('select', function () {
                    attachment = file_frame.state().get('selection').first().toJSON();

                    self.prev('.wpsa-url').val(attachment.url).change();
                });