.../ProxyClass/SmartCache/DefaultRequestPolicy.php | 92 ----------------------
 .../src/EventSubscriber/SmartCacheSubscriber.php   | 38 ++++++---
 2 files changed, 27 insertions(+), 103 deletions(-)

diff --git a/core/lib/Drupal/Core/ProxyClass/SmartCache/DefaultRequestPolicy.php b/core/lib/Drupal/Core/ProxyClass/SmartCache/DefaultRequestPolicy.php
deleted file mode 100644
index 2fdebb5..0000000
--- a/core/lib/Drupal/Core/ProxyClass/SmartCache/DefaultRequestPolicy.php
+++ /dev/null
@@ -1,92 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains Drupal\Core\ProxyClass\SmartCache\DefaultRequestPolicy.
- */
-
-/**
- * This file was generated via php core/scripts/generate-proxy-class.php 'Drupal\Core\SmartCache\DefaultRequestPolicy' "core/lib/Drupal/Core".
- */
-
-namespace Drupal\Core\ProxyClass\SmartCache {
-
-    /**
-     * Provides a proxy class for \Drupal\Core\SmartCache\DefaultRequestPolicy.
-     *
-     * @see \Drupal\Component\ProxyBuilder
-     */
-    class DefaultRequestPolicy implements \Drupal\Core\PageCache\ChainRequestPolicyInterface
-    {
-
-        use \Drupal\Core\DependencyInjection\DependencySerializationTrait;
-
-        /**
-         * The id of the original proxied service.
-         *
-         * @var string
-         */
-        protected $drupalProxyOriginalServiceId;
-
-        /**
-         * The real proxied service, after it was lazy loaded.
-         *
-         * @var \Drupal\Core\SmartCache\DefaultRequestPolicy
-         */
-        protected $service;
-
-        /**
-         * The service container.
-         *
-         * @var \Symfony\Component\DependencyInjection\ContainerInterface
-         */
-        protected $container;
-
-        /**
-         * Constructs a ProxyClass Drupal proxy object.
-         *
-         * @param \Symfony\Component\DependencyInjection\ContainerInterface $container
-         *   The container.
-         * @param string $drupal_proxy_original_service_id
-         *   The service ID of the original service.
-         */
-        public function __construct(\Symfony\Component\DependencyInjection\ContainerInterface $container, $drupal_proxy_original_service_id)
-        {
-            $this->container = $container;
-            $this->drupalProxyOriginalServiceId = $drupal_proxy_original_service_id;
-        }
-
-        /**
-         * Lazy loads the real service from the container.
-         *
-         * @return object
-         *   Returns the constructed real service.
-         */
-        protected function lazyLoadItself()
-        {
-            if (!isset($this->service)) {
-                $this->service = $this->container->get($this->drupalProxyOriginalServiceId);
-            }
-
-            return $this->service;
-        }
-
-        /**
-         * {@inheritdoc}
-         */
-        public function check(\Symfony\Component\HttpFoundation\Request $request)
-        {
-            return $this->lazyLoadItself()->check($request);
-        }
-
-        /**
-         * {@inheritdoc}
-         */
-        public function addPolicy(\Drupal\Core\PageCache\RequestPolicyInterface $policy)
-        {
-            return $this->lazyLoadItself()->addPolicy($policy);
-        }
-
-    }
-
-}
diff --git a/core/modules/smart_cache/src/EventSubscriber/SmartCacheSubscriber.php b/core/modules/smart_cache/src/EventSubscriber/SmartCacheSubscriber.php
index 2e58521..9f9fe33 100644
--- a/core/modules/smart_cache/src/EventSubscriber/SmartCacheSubscriber.php
+++ b/core/modules/smart_cache/src/EventSubscriber/SmartCacheSubscriber.php
@@ -46,7 +46,23 @@ class SmartCacheSubscriber implements EventSubscriberInterface {
    * @see onRouteMatch()
    * @see onRespond()
    */
-  const SMART_CACHE_REQUEST_POLICY_RESULT = '_smart_cache_request_policy_result';
+  const ATTRIBUTE_REQUEST_POLICY_RESULT = '_smart_cache_request_policy_result';
+
+  /**
+   * Attribute name of the Smart Cache cache contexts for the current route CID.
+   *
+   * @see onRouteMatch()
+   * @see onRespond()
+   */
+  const ATTRIBUTE_CACHE_CONTEXTS_FOR_ROUTE_CID = '_smart_cache_cache_contexts_for_route_cid';
+
+  /**
+   * Attribute name of the Smart Cache cache contexts for the current route.
+   *
+   * @see onRouteMatch()
+   * @see onRespond()
+   */
+  const ATTRIBUTE_CACHE_CONTEXTS_FOR_ROUTE = '_smart_cache_cache_contexts_for_route';
 
   /**
    * The cache contexts manager.
@@ -117,7 +133,7 @@ public function onRouteMatch(GetResponseEvent $event) {
     // not have to redo the request policy check.
     $request = $event->getRequest();
     $request_policy_result = $this->requestPolicy->check($request);
-    $event->getRequest()->attributes->set(self::SMART_CACHE_REQUEST_POLICY_RESULT, $request_policy_result);
+    $request->attributes->set(self::ATTRIBUTE_REQUEST_POLICY_RESULT, $request_policy_result);
     if ($request_policy_result === RequestPolicyInterface::DENY) {
       return;
     }
@@ -125,6 +141,8 @@ public function onRouteMatch(GetResponseEvent $event) {
     // Get the contexts by which the current route's response must be varied.
     $cid = implode(':', $this->cacheContextsManager->convertTokensToKeys(['route'])->getKeys());
     $cache_contexts_for_route = $this->smartContextsCache->get($cid);
+    $request->attributes->set(self::ATTRIBUTE_CACHE_CONTEXTS_FOR_ROUTE_CID, $cid);
+    $request->attributes->set(self::ATTRIBUTE_CACHE_CONTEXTS_FOR_ROUTE, $cache_contexts_for_route);
 
     // Get & set the cached HTML response for the current route, if any.
     if ($cache_contexts_for_route !== FALSE) {
@@ -164,17 +182,10 @@ public function onResponse(FilterResponseEvent $event) {
     // policies are not met.
     // @see onRouteMatch()
     $request = $event->getRequest();
-    if ($request->attributes->get(self::SMART_CACHE_REQUEST_POLICY_RESULT) === RequestPolicyInterface::DENY || $this->responsePolicy->check($response, $request) === ResponsePolicyInterface::DENY) {
+    if ($request->attributes->get(self::ATTRIBUTE_REQUEST_POLICY_RESULT) === RequestPolicyInterface::DENY || $this->responsePolicy->check($response, $request) === ResponsePolicyInterface::DENY) {
       return;
     }
 
-    // Get the contexts by which the current route's response must be varied.
-    $contexts_cid = $this->cacheContextsManager->convertTokensToKeys(['route'])->getKeys()[0];
-    $stored_cache_contexts = $this->smartContextsCache->get($contexts_cid);
-    if ($stored_cache_contexts !== FALSE) {
-      $stored_cache_contexts = $stored_cache_contexts->data;
-    }
-
     // Get the cacheability metadata.
     $html_cacheability = CacheableMetadata::createFromObject($response->getCacheableMetadata())
       ->addCacheContexts(['route'])
@@ -190,6 +201,11 @@ public function onResponse(FilterResponseEvent $event) {
     // SmartCache only caches cacheable HTML responses, i.e. with a max-age > 0.
     if ($html_cacheability->getCacheMaxAge() !== 0) {
       $this->normalizeCacheability($html_cacheability);
+
+      // Get the contexts by which the current route's response must be varied.
+      $cache_contexts_for_route = $request->attributes->get(self::ATTRIBUTE_CACHE_CONTEXTS_FOR_ROUTE);
+      $stored_cache_contexts = ($cache_contexts_for_route !== FALSE) ? $cache_contexts_for_route->data : NULL;
+
       // If the set of cache contexts is different, store the union of the
       // already stored cache contexts and the contexts for this request.
       if ($html_cacheability->getCacheContexts() !== $stored_cache_contexts) {
@@ -197,7 +213,7 @@ public function onResponse(FilterResponseEvent $event) {
           $html_cacheability->addCacheContexts($stored_cache_contexts);
           $this->normalizeCacheability($html_cacheability);
         }
-        $this->smartContextsCache->set($contexts_cid, $html_cacheability->getCacheContexts());
+        $this->smartContextsCache->set($request->attributes->get(self::ATTRIBUTE_CACHE_CONTEXTS_FOR_ROUTE_CID), $html_cacheability->getCacheContexts());
       }
 
       // Finally, cache the HTML response by those contexts.