Merge branch 'MAGETWO-55054-patch20' into bugfixes20

Author: Olexandr Lysenko

app/code/Magento/Catalog/Controller/Adminhtml/Product/Action/Attribute/Save.php

@@ -132,7 +132,7 @@ public function execute()
                         $attributesData[$attributeCode] = $value;
                     } elseif ($attribute->getFrontendInput() == 'multiselect') {
                         // Check if 'Change' checkbox has been checked by admin for this attribute
-                        $isChanged = (bool)$this->getRequest()->getPost($attributeCode . '_checkbox');
+                        $isChanged = (bool)$this->getRequest()->getPost('toggle_' . $attributeCode);
                         if (!$isChanged) {
                             unset($attributesData[$attributeCode]);
                             continue;