def button_for_js(label, js, html_options={})
      tag(:input, {type: 'button', value: label, onClick: js}.merge(
        html_options))
    end
def button_for_js(label, js, html_options={})
      tag(:input, {type: 'button', value: label, onClick: js}.merge(
        html_options))
    end
replacement of button_to_function to avoid DEPRECATION WARNING.

 When the js is called just once, onClick is simpler than
 unobtrusive-javascript approach.