ENGCOM-1554: [Backport 2.1] Fix for displaying a negative price for a custom option #15203

 - Merge Pull Request #15203 from dverkade/magento2:2.1-Fix-negative-value-for-custom-option
 - Merged commits:
   1. c224ad0

Author: magento-engcom-team

app/code/Magento/Catalog/view/base/web/js/price-options.js

@@ -19,8 +19,10 @@ define([
         optionConfig: {},
         optionHandlers: {},
         optionTemplate: '<%= data.label %>' +
-        '<% if (data.finalPrice.value) { %>' +
+        '<% if (data.finalPrice.value > 0) { %>' +
         ' +<%- data.finalPrice.formatted %>' +
+        '<% } else if (data.finalPrice.value < 0) { %>' +
+        ' <%- data.finalPrice.formatted %>' +
         '<% } %>',
         controlContainer: 'dd'
     };