Input field selector widget should display multiple fields instead of always aggregating with a count
Input field selector widget allows you to select multiple fields with a checkbox. However, when you select multiple fields, it always only displays a single field, with an additional +(count-1) text to indicate that more fields have been selected. Although this is needed, it shouldn't be the default behavior. By default, the widget should try to display all the selected fields, and only summarize it if it runs out of space.