bugfix - customer emails are not being sent from admin if customer is assiged to store "0". "0" should be considered a valid store id

Author: matheusgontijo

app/code/Magento/Customer/Model/EmailNotification.php

@@ -167,7 +167,7 @@ public function credentialsChanged(
     private function emailAndPasswordChanged(CustomerInterface $customer, $email)
     {
         $storeId = $customer->getStoreId();
-        if (!$storeId) {
+        if ($storeId === null) {
             $storeId = $this->getWebsiteStoreId($customer);
         }
 
@@ -193,7 +193,7 @@ private function emailAndPasswordChanged(CustomerInterface $customer, $email)
     private function emailChanged(CustomerInterface $customer, $email)
     {
         $storeId = $customer->getStoreId();
-        if (!$storeId) {
+        if ($storeId === null) {
             $storeId = $this->getWebsiteStoreId($customer);
         }
 
@@ -218,7 +218,7 @@ private function emailChanged(CustomerInterface $customer, $email)
     private function passwordReset(CustomerInterface $customer)
     {
         $storeId = $customer->getStoreId();
-        if (!$storeId) {
+        if ($storeId === null) {
             $storeId = $this->getWebsiteStoreId($customer);
         }
 
@@ -317,7 +317,7 @@ private function getWebsiteStoreId($customer, $defaultStoreId = null)
     public function passwordReminder(CustomerInterface $customer)
     {
         $storeId = $customer->getStoreId();
-        if (!$storeId) {
+        if ($storeId === null) {
             $storeId = $this->getWebsiteStoreId($customer);
         }
 
@@ -341,7 +341,7 @@ public function passwordReminder(CustomerInterface $customer)
     public function passwordResetConfirmation(CustomerInterface $customer)
     {
         $storeId = $customer->getStoreId();
-        if (!$storeId) {
+        if ($storeId === null) {
             $storeId = $this->getWebsiteStoreId($customer);
         }
 
@@ -382,7 +382,7 @@ public function newAccount(
             );
         }
 
-        if (!$storeId) {
+        if ($storeId === null) {
             $storeId = $this->getWebsiteStoreId($customer, $sendemailStoreId);
         }