MAGETWO-81329: Escape $ in cms page/static block content #11315

 - Merge Pull Request #11315 from slackerzz/magento2:fix_issue_10501
 - Merged commits:
   1. bac9576

Author: orlangur

lib/web/mage/utils/template.js

@@ -76,7 +76,11 @@ define([
      * @returns {Boolean}
      */
     function isTemplate(value) {
-        return typeof value === 'string' && ~value.indexOf(opener);
+        return typeof value === 'string' &&
+            value.indexOf(opener) !== -1 &&
+            // the below pattern almost always indicates an accident which should not cause template evaluation
+            // refuse to evaluate
+            value.indexOf('${{') === -1;
     }
 
     /**