MAGETWO-35610: Merge and Fix Tests

 - Code style changes to fix L3

Author: marcozheng

app/code/Magento/Email/Test/Unit/Model/TemplateTest.php

@@ -542,7 +542,8 @@ public function getPreparedTemplateTextProvider()
                 'templateType' => \Magento\Framework\App\TemplateTypesInterface::TYPE_HTML,
                 'templateStyles' => '.body { color: orange }',
                 'templateText' => 'template text',
-                'expectedResult' => '<style type="text/css">' . "\n.body { color: orange }\n</style>\n" . 'template text',
+                'expectedResult' =>
+                    '<style type="text/css">' . "\n.body { color: orange }\n</style>\n" . 'template text',
             ],
         ];
     }

app/code/Magento/GiftMessage/Model/Plugin/OrderSave.php

@@ -61,7 +61,7 @@ public function aroundSave(
      */
     protected function saveOrderGiftMessage(\Magento\Sales\Api\Data\OrderInterface $order)
     {
-        if (!is_null($order->getExtensionAttributes())) {
+        if (null !== ($order->getExtensionAttributes())) {
             /* @var \Magento\GiftMessage\Api\Data\MessageInterface $giftMessage */
             $giftMessage = $order->getExtensionAttributes()->getGiftMessage();
             try {
@@ -84,7 +84,7 @@ protected function saveOrderItemGiftMessage(\Magento\Sales\Api\Data\OrderInterfa
         if (null !== $order->getItems()) {
             /** @var \Magento\Sales\Api\Data\OrderItemInterface $orderItem */
             foreach ($order->getItems() as $orderItem) {
-                if (!is_null($orderItem->getExtensionAttributes())) {
+                if (null !== ($orderItem->getExtensionAttributes())) {
                     /* @var \Magento\GiftMessage\Api\Data\MessageInterface $giftMessage */
                     $giftMessage = $orderItem->getExtensionAttributes()->getGiftMessage();
                     try {