MAGETWO-64885: Wrong cookies set for store views with multidomain

Author: nikshostko

app/code/Magento/Store/Block/Switcher.php

@@ -224,7 +224,7 @@ public function getTargetStorePostData(\Magento\Store\Model\Store $store, $data
     {
         $data[\Magento\Store\Api\StoreResolverInterface::PARAM_NAME] = $store->getCode();
         return $this->_postDataHelper->getPostData(
-            $this->getUrl('stores/store/switch'),
+            $store->getCurrentUrl(false),
             $data
         );
     }

app/code/Magento/Store/Model/Plugin/StoreCookie.php

@@ -12,6 +12,8 @@
 use Magento\Store\Model\StoreIsInactiveException;
 use Magento\Framework\Exception\NoSuchEntityException;
 use \InvalidArgumentException;
+use Magento\Store\Api\StoreResolverInterface;
+use Magento\Framework\App\ObjectManager;
 
 /**
  * Class StoreCookie
@@ -33,19 +35,27 @@ class StoreCookie
      */
     protected $storeRepository;
 
+    /**
+     * @var StoreResolverInterface
+     */
+    private $storeResolver;
+
     /**
      * @param StoreManagerInterface $storeManager
      * @param StoreCookieManagerInterface $storeCookieManager
      * @param StoreRepositoryInterface $storeRepository
+     * @param StoreResolverInterface $storeResolver
      */
     public function __construct(
         StoreManagerInterface $storeManager,
         StoreCookieManagerInterface $storeCookieManager,
-        StoreRepositoryInterface $storeRepository
+        StoreRepositoryInterface $storeRepository,
+        StoreResolverInterface $storeResolver = null
     ) {
         $this->storeManager = $storeManager;
         $this->storeCookieManager = $storeCookieManager;
         $this->storeRepository = $storeRepository;
+        $this->storeResolver = $storeResolver ?: ObjectManager::getInstance()->get(StoreResolverInterface::class);
     }
 
     /**
@@ -72,5 +82,13 @@ public function beforeDispatch(
                 $this->storeCookieManager->deleteStoreCookie($this->storeManager->getDefaultStoreView());
             }
         }
+        if (
+            $this->storeCookieManager->getStoreCodeFromCookie() === null
+            || $request->getParam(StoreResolverInterface::PARAM_NAME) !== null
+        ) {
+            $storeId = $this->storeResolver->getCurrentStoreId();
+            $store = $this->storeRepository->getActiveStoreById($storeId);
+            $this->storeCookieManager->setStoreCookie($store);
+        }
     }
 }