ENGCOM-2270: Smallest codestyle fix in Option/Type/Text.php #16566

 - Merge Pull Request #16566 from aitoc/magento2:option-type-fix
 - Merged commits:
   1. 5679e14

app/code/Magento/Catalog/Model/Product/Option/Type/Text.php

@@ -81,7 +81,7 @@ public function validateUserValue($values)
      */
     public function prepareForCart()
     {
-        if ($this->getIsValid() && strlen($this->getUserValue()) > 0) {
+        if ($this->getIsValid() && ($this->getUserValue() !== '')) {
             return $this->getUserValue();
         } else {
             return null;