[FIX] Empty binary column download error

In case of an empty inline column, a Download link inviting the user to
click would still be rendered (erroring out if the user eventually
clicked on it)

fixes #3684

addons/web/static/src/js/view_list.js

@@ -2235,7 +2235,7 @@ instance.web.list.Column = instance.web.Class.extend({
         }
         if (attrs.invisible) { return ''; }
 
-        if (!row_data[this.id]) {
+        if (!(row_data[this.id] && row_data[this.id].value)) {
             return options.value_if_empty === undefined
                     ? ''
                     : options.value_if_empty;