diff --git a/composer.lock b/composer.lock
index 3b126299e4..e298fe0344 100644
--- a/composer.lock
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@@ -1798,29 +1870,88 @@
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+            "time": "2017-10-11T12:05:26+00:00"
+        },
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+                    "email": "p@tchwork.com"
+                },
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@@ -1907,36 +2038,39 @@
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@@ -2094,7 +2235,7 @@
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@@ -2121,40 +2262,47 @@
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             "description": "Symfony Translation Component",
             "homepage": "https://symfony.com",
-            "time": "2017-04-12T14:13:17+00:00"
+            "time": "2018-01-03T07:37:34+00:00"
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-            "version": "v3.2.8",
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@@ -2165,13 +2313,13 @@
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                 "symfony/intl": "",
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@@ -2198,27 +2346,30 @@
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@@ -4019,25 +4170,25 @@
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             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/css-selector/zipball/02983c144038e697c959e6b06ef6666de759ccbc",
-                "reference": "02983c144038e697c959e6b06ef6666de759ccbc",
+                "url": "https://api.github.com/repos/symfony/css-selector/zipball/e66394bc7610e69279bfdb3ab11b4fe65403f556",
+                "reference": "e66394bc7610e69279bfdb3ab11b4fe65403f556",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9"
+                "php": "^5.5.9|>=7.0.8"
             },
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.2-dev"
+                    "dev-master": "3.4-dev"
                 }
             },
             "autoload": {
@@ -4125,28 +4276,28 @@
             ],
             "description": "Symfony CssSelector Component",
             "homepage": "https://symfony.com",
-            "time": "2017-05-01T14:55:58+00:00"
+            "time": "2018-01-03T07:37:34+00:00"
         },
         {
             "name": "symfony/dom-crawler",
-            "version": "v3.2.8",
+            "version": "v3.4.3",
             "source": {
                 "type": "git",
                 "url": "https://github.com/symfony/dom-crawler.git",
-                "reference": "f1ad34e8af09ed17570e027cf0c58a12eddec286"
+                "reference": "09bd97b844b3151fab82f2fdd62db9c464b3910a"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/symfony/dom-crawler/zipball/f1ad34e8af09ed17570e027cf0c58a12eddec286",
-                "reference": "f1ad34e8af09ed17570e027cf0c58a12eddec286",
+                "url": "https://api.github.com/repos/symfony/dom-crawler/zipball/09bd97b844b3151fab82f2fdd62db9c464b3910a",
+                "reference": "09bd97b844b3151fab82f2fdd62db9c464b3910a",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.5.9",
+                "php": "^5.5.9|>=7.0.8",
                 "symfony/polyfill-mbstring": "~1.0"
             },
             "require-dev": {
-                "symfony/css-selector": "~2.8|~3.0"
+                "symfony/css-selector": "~2.8|~3.0|~4.0"
             },
             "suggest": {
                 "symfony/css-selector": ""
@@ -4154,7 +4305,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.2-dev"
+                    "dev-master": "3.4-dev"
                 }
             },
             "autoload": {
@@ -4181,7 +4332,7 @@
             ],
             "description": "Symfony DomCrawler Component",
             "homepage": "https://symfony.com",
-            "time": "2017-04-12T14:13:17+00:00"
+            "time": "2018-01-03T07:37:34+00:00"
         },
         {
             "name": "symfony/phpunit-bridge",
@@ -4258,7 +4409,7 @@
     "prefer-stable": true,
     "prefer-lowest": false,
     "platform": {
-        "php": ">=5.5.9"
+        "php": "^5.5.9|>=7.0.8"
     },
     "platform-dev": []
 }
diff --git a/core/composer.json b/core/composer.json
index aeb15b4d4d..2e1b1c29dd 100644
--- a/core/composer.json
+++ b/core/composer.json
@@ -4,20 +4,20 @@
     "type": "drupal-core",
     "license": "GPL-2.0+",
     "require": {
-        "php": ">=5.5.9",
-        "symfony/class-loader": "~3.2.8",
-        "symfony/console": "~3.2.8",
-        "symfony/dependency-injection": "~3.2.8",
-        "symfony/event-dispatcher": "~3.2.8",
-        "symfony/http-foundation": "~3.2.8",
-        "symfony/http-kernel": "~3.2.8",
-        "symfony/routing": "~3.2.8",
-        "symfony/serializer": "~3.2.8",
-        "symfony/translation": "~3.2.8",
-        "symfony/validator": "~3.2.8",
-        "symfony/process": "~3.2.8",
+        "php": "^5.5.9|>=7.0.8",
+        "symfony/class-loader": "~3.4.0",
+        "symfony/console": "~3.4.0",
+        "symfony/dependency-injection": "~3.4.0",
+        "symfony/event-dispatcher": "~3.4.0",
+        "symfony/http-foundation": "~3.4.0",
+        "symfony/http-kernel": "~3.4.0",
+        "symfony/routing": "~3.4.0",
+        "symfony/serializer": "~3.4.0",
+        "symfony/translation": "~3.4.0",
+        "symfony/validator": "~3.4.0",
+        "symfony/process": "~3.4.0",
         "symfony/polyfill-iconv": "^1.0",
-        "symfony/yaml": "~3.2.8",
+        "symfony/yaml": "~3.4.0",
         "twig/twig": "^1.35.0",
         "doctrine/common": "^2.5",
         "doctrine/annotations": "^1.2",
@@ -46,8 +46,9 @@
         "mikey179/vfsStream": "^1.2",
         "phpunit/phpunit": "^4.8.35 || ^6.1",
         "phpspec/prophecy": "^1.4",
-        "symfony/css-selector": "~3.2.8",
-        "symfony/phpunit-bridge": "^3.4.3"
+        "symfony/css-selector": "^3.4.0",
+        "symfony/phpunit-bridge": "^3.4.3",
+        "symfony/debug": "^3.4.0"
     },
     "replace": {
         "drupal/action": "self.version",
diff --git a/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php b/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php
index a23f333a0a..8b73b9a1d1 100644
--- a/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php
+++ b/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php
@@ -104,8 +104,11 @@ public function dispatch($event_name, Event $event = NULL) {
           if (!isset($definition['callable'])) {
             $definition['callable'] = [$this->container->get($definition['service'][0]), $definition['service'][1]];
           }
+          if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure) {
+            $definition['callable'][0] = $definition['callable'][0]();
+          }
 
-          $definition['callable']($event, $event_name, $this);
+          call_user_func($definition['callable'], $event, $event_name, $this);
           if ($event->isPropagationStopped()) {
             return $event;
           }
@@ -144,6 +147,9 @@ public function getListeners($event_name = NULL) {
           if (!isset($definition['callable'])) {
             $definition['callable'] = [$this->container->get($definition['service'][0]), $definition['service'][1]];
           }
+          if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure) {
+            $definition['callable'][0] = $definition['callable'][0]();
+          }
 
           $result[] = $definition['callable'];
         }
@@ -156,27 +162,29 @@ public function getListeners($event_name = NULL) {
   /**
    * {@inheritdoc}
    */
-  public function getListenerPriority($eventName, $listener) {
-    // Parts copied from \Symfony\Component\EventDispatcher, that's why you see
-    // a yoda condition here.
-    if (!isset($this->listeners[$eventName])) {
+  public function getListenerPriority($event_name, $listener) {
+    if (!isset($this->listeners[$event_name])) {
       return;
     }
-    foreach ($this->listeners[$eventName] as $priority => $listeners) {
-      if (FALSE !== ($key = array_search(['callable' => $listener], $listeners, TRUE))) {
-        return $priority;
-      }
+    if (is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
+      $listener[0] = $listener[0]();
     }
     // Resolve service definitions if the listener has not been found so far.
-    foreach ($this->listeners[$eventName] as $priority => &$definitions) {
+    foreach ($this->listeners[$event_name] as $priority => &$definitions) {
       foreach ($definitions as $key => &$definition) {
         if (!isset($definition['callable'])) {
           // Once the callable is retrieved we keep it for subsequent method
           // invocations on this class.
-          $definition['callable'] = [$this->container->get($definition['service'][0]), $definition['service'][1]];
-          if ($definition['callable'] === $listener) {
-            return $priority;
-          }
+          $definition['callable'] = [
+            $this->container->get($definition['service'][0]),
+            $definition['service'][1],
+          ];
+        }
+        if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure) {
+          $definition['callable'][0] = $definition['callable'][0]();
+        }
+        if ($definition['callable'] === $listener) {
+          return $priority;
         }
       }
     }
@@ -186,7 +194,32 @@ public function getListenerPriority($eventName, $listener) {
    * {@inheritdoc}
    */
   public function hasListeners($event_name = NULL) {
-    return (bool) count($this->getListeners($event_name));
+    if ($event_name !== NULL) {
+      if (empty($this->listeners[$event_name])) {
+        return FALSE;
+      }
+      else {
+        foreach ($this->listeners[$event_name] as $priority => $listeners) {
+          if (!empty($listeners)) {
+            return TRUE;
+          }
+        }
+        return FALSE;
+      }
+    }
+    if (!empty($this->listeners)) {
+      foreach ($this->listeners as $event_name => $event_listeners) {
+        if (!empty($event_listeners)) {
+          foreach ($event_listeners as $priority => $listeners) {
+            if (!empty($listeners)) {
+              return TRUE;
+            }
+          }
+        }
+        return FALSE;
+      }
+    }
+    return FALSE;
   }
 
   /**
@@ -214,6 +247,13 @@ public function removeListener($event_name, $listener) {
           $definition['callable'] = [$this->container->get($definition['service'][0]), $definition['service'][1]];
         }
 
+        if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure && !$listener instanceof \Closure) {
+          $definition['callable'][0] = $definition['callable'][0]();
+        }
+
+        if (is_array($definition['callable']) && isset($definition['callable'][0]) && !$definition['callable'][0] instanceof \Closure && is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
+          $listener[0] = $listener[0]();
+        }
         if ($definition['callable'] === $listener) {
           unset($this->listeners[$event_name][$priority][$key]);
         }
diff --git a/core/lib/Drupal/Component/Serialization/YamlSymfony.php b/core/lib/Drupal/Component/Serialization/YamlSymfony.php
index d35e09cd48..efe3039df7 100644
--- a/core/lib/Drupal/Component/Serialization/YamlSymfony.php
+++ b/core/lib/Drupal/Component/Serialization/YamlSymfony.php
@@ -34,7 +34,7 @@ public static function decode($raw) {
       $yaml = new Parser();
       // Make sure we have a single trailing newline. A very simple config like
       // 'foo: bar' with no newline will fail to parse otherwise.
-      return $yaml->parse($raw, SymfonyYaml::PARSE_EXCEPTION_ON_INVALID_TYPE);
+      return $yaml->parse($raw, SymfonyYaml::PARSE_EXCEPTION_ON_INVALID_TYPE | SymfonyYaml::PARSE_KEYS_AS_STRINGS);
     }
     catch (\Exception $e) {
       throw new InvalidDataTypeException($e->getMessage(), $e->getCode(), $e);
diff --git a/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php b/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php
index e0becc71e2..2c4d0d6832 100644
--- a/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php
+++ b/core/lib/Drupal/Core/DependencyInjection/ContainerBuilder.php
@@ -85,7 +85,10 @@ public function register($id, $class = null) {
     if (strtolower($id) !== $id) {
       throw new \InvalidArgumentException("Service ID names must be lowercase: $id");
     }
-    return parent::register($id, $class);
+    $definition = parent::register($id, $class);
+    // As of Symfony 3.4 all services are private by default.
+    $definition->setPublic(TRUE);
+    return $definition;
   }
 
   /**
diff --git a/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php b/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php
index d999450b0a..9df17dd8d1 100644
--- a/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php
+++ b/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php
@@ -158,6 +158,8 @@ private function parseDefinition($id, $service, $file)
             $definition = new DefinitionDecorator($service['parent']);
         } else {
             $definition = new Definition();
+            // As of Symfony 3.4 all services are private by default.
+            $definition->setPublic(TRUE);
         }
 
         if (isset($service['class'])) {
diff --git a/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php b/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php
index e3e4895efe..cf4cd89cb5 100644
--- a/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php
+++ b/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php
@@ -59,23 +59,23 @@ public static function setSettingsOnRequest(Request $request, Settings $settings
     // Initialize proxy settings.
     if ($settings->get('reverse_proxy', FALSE)) {
       $ip_header = $settings->get('reverse_proxy_header', 'X_FORWARDED_FOR');
-      $request::setTrustedHeaderName($request::HEADER_CLIENT_IP, $ip_header);
+      $request::setTrustedHeaderName($request::HEADER_X_FORWARDED_FOR, $ip_header);
 
       $proto_header = $settings->get('reverse_proxy_proto_header', 'X_FORWARDED_PROTO');
-      $request::setTrustedHeaderName($request::HEADER_CLIENT_PROTO, $proto_header);
+      $request::setTrustedHeaderName($request::HEADER_X_FORWARDED_PROTO, $proto_header);
 
       $host_header = $settings->get('reverse_proxy_host_header', 'X_FORWARDED_HOST');
-      $request::setTrustedHeaderName($request::HEADER_CLIENT_HOST, $host_header);
+      $request::setTrustedHeaderName($request::HEADER_X_FORWARDED_HOST, $host_header);
 
       $port_header = $settings->get('reverse_proxy_port_header', 'X_FORWARDED_PORT');
-      $request::setTrustedHeaderName($request::HEADER_CLIENT_PORT, $port_header);
+      $request::setTrustedHeaderName($request::HEADER_X_FORWARDED_PORT, $port_header);
 
       $forwarded_header = $settings->get('reverse_proxy_forwarded_header', 'FORWARDED');
       $request::setTrustedHeaderName($request::HEADER_FORWARDED, $forwarded_header);
 
       $proxies = $settings->get('reverse_proxy_addresses', []);
       if (count($proxies) > 0) {
-        $request::setTrustedProxies($proxies);
+        $request::setTrustedProxies($proxies, Request::HEADER_X_FORWARDED_ALL | Request::HEADER_FORWARDED);
       }
     }
   }
diff --git a/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php b/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php
index a750ecaf09..ec573d2786 100644
--- a/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php
+++ b/core/tests/Drupal/Tests/Component/EventDispatcher/ContainerAwareEventDispatcherTest.php
@@ -23,6 +23,7 @@
  * @see https://github.com/symfony/symfony/pull/12521
  *
  * @group EventDispatcher
+ * @group legacy
  */
 class ContainerAwareEventDispatcherTest extends SymfonyContainerAwareEventDispatcherTest
 {
@@ -193,4 +194,52 @@ public function testGetListenerPriorityWithServices()
         $this->assertSame(5, $actualPriority);
     }
 
+    /**
+     * @expectedDeprecation The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.
+     */
+    public function testAddAListenerService() {
+      parent::testAddAListenerService();
+    }
+
+    /**
+     * @expectedDeprecation The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.
+     */
+    public function testPreventDuplicateListenerService() {
+      parent::testPreventDuplicateListenerService();
+    }
+
+    /**
+     * @expectedDeprecation The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.
+     */
+    public function testAddASubscriberService() {
+      parent::testAddASubscriberService();
+    }
+
+    /**
+     * @expectedDeprecation The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.
+     */
+    public function testHasListenersOnLazyLoad() {
+      parent::testHasListenersOnLazyLoad();
+    }
+
+    /**
+     * @expectedDeprecation The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.
+     */
+    public function testGetListenersOnLazyLoad() {
+      parent::testGetListenersOnLazyLoad();
+    }
+
+    /**
+     * @expectedDeprecation The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.
+     */
+    public function testRemoveAfterDispatch() {
+      parent::testRemoveAfterDispatch();
+    }
+
+    /**
+     * @expectedDeprecation The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.
+     */
+    public function testRemoveBeforeDispatch() {
+      parent::testRemoveBeforeDispatch();
+    }
  }
diff --git a/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php b/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php
index becd7c0221..b653efd1fd 100644
--- a/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php
+++ b/core/tests/Drupal/Tests/Component/Serialization/YamlTest.php
@@ -12,6 +12,7 @@
 /**
  * @coversDefaultClass \Drupal\Component\Serialization\Yaml
  * @group Serialization
+ * @group legacy
  */
 class YamlTest extends TestCase {
 
@@ -80,6 +81,8 @@ public function testYamlFiles($file) {
    * Ensures that decoding php objects is similar for PECL and Symfony.
    *
    * @requires extension yaml
+   *
+   * @expectedDeprecation Using the unquoted scalar value "!php/object "O:8:\"stdClass\":1:{s:3:\"foo\";s:3:\"bar\";}"" is deprecated since version 3.3 and will be considered as a tagged value in 4.0. You must quote it on line 2.
    */
   public function testObjectSupportDisabled() {
     $object = new \stdClass();
diff --git a/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/ProxyServicesPassTest.php b/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/ProxyServicesPassTest.php
index aea2524ebf..638bd1512e 100644
--- a/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/ProxyServicesPassTest.php
+++ b/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/ProxyServicesPassTest.php
@@ -39,7 +39,7 @@ public function testContainerWithoutLazyServices() {
 
     $this->proxyServicesPass->process($container);
 
-    $this->assertCount(1, $container->getDefinitions());
+    $this->assertCount(2, $container->getDefinitions());
     $this->assertEquals('Drupal\Core\Plugin\CachedDiscoveryClearer', $container->getDefinition('plugin_cache_clearer')->getClass());
   }
 
@@ -53,7 +53,7 @@ public function testContainerWithLazyServices() {
 
     $this->proxyServicesPass->process($container);
 
-    $this->assertCount(2, $container->getDefinitions());
+    $this->assertCount(3, $container->getDefinitions());
 
     $non_proxy_definition = $container->getDefinition('drupal.proxy_original_service.plugin_cache_clearer');
     $this->assertEquals('Drupal\Core\Plugin\CachedDiscoveryClearer', $non_proxy_definition->getClass());
diff --git a/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/TaggedHandlersPassTest.php b/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/TaggedHandlersPassTest.php
index 5fe2b4478c..848c458a75 100644
--- a/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/TaggedHandlersPassTest.php
+++ b/core/tests/Drupal/Tests/Core/DependencyInjection/Compiler/TaggedHandlersPassTest.php
@@ -38,7 +38,7 @@ public function testProcessNoConsumers() {
     $handler_pass = new TaggedHandlersPass();
     $handler_pass->process($container);
 
-    $this->assertCount(1, $container->getDefinitions());
+    $this->assertCount(2, $container->getDefinitions());
     $this->assertFalse($container->getDefinition('consumer_id')->hasMethodCall('addHandler'));
   }
 
diff --git a/core/tests/Drupal/Tests/Core/StackMiddleware/ReverseProxyMiddlewareTest.php b/core/tests/Drupal/Tests/Core/StackMiddleware/ReverseProxyMiddlewareTest.php
index b7a784d487..c42ff5c028 100644
--- a/core/tests/Drupal/Tests/Core/StackMiddleware/ReverseProxyMiddlewareTest.php
+++ b/core/tests/Drupal/Tests/Core/StackMiddleware/ReverseProxyMiddlewareTest.php
@@ -47,6 +47,10 @@ public function testNoProxy() {
    * Tests that subscriber sets trusted headers when reverse proxy is set.
    *
    * @dataProvider reverseProxyEnabledProvider
+   *
+   * @group legacy
+   *
+   * @expectedDeprecation The "Symfony\Component\HttpFoundation\Request::setTrustedHeaderName()" method is deprecated since version 3.3 and will be removed in 4.0. Use the $trustedHeaderSet argument of the Request::setTrustedProxies() method instead.
    */
   public function testReverseProxyEnabled($provided_settings) {
     // Enable reverse proxy and add test values.
@@ -87,10 +91,10 @@ protected function trustedHeadersAreSet(Settings $settings) {
     $request = new Request();
 
     $middleware->handle($request);
-    $this->assertSame($settings->get('reverse_proxy_header'), $request->getTrustedHeaderName($request::HEADER_CLIENT_IP));
-    $this->assertSame($settings->get('reverse_proxy_proto_header'), $request->getTrustedHeaderName($request::HEADER_CLIENT_PROTO));
-    $this->assertSame($settings->get('reverse_proxy_host_header'), $request->getTrustedHeaderName($request::HEADER_CLIENT_HOST));
-    $this->assertSame($settings->get('reverse_proxy_port_header'), $request->getTrustedHeaderName($request::HEADER_CLIENT_PORT));
+    $this->assertSame($settings->get('reverse_proxy_header'), $request->getTrustedHeaderName($request::HEADER_X_FORWARDED_FOR));
+    $this->assertSame($settings->get('reverse_proxy_proto_header'), $request->getTrustedHeaderName($request::HEADER_X_FORWARDED_PROTO));
+    $this->assertSame($settings->get('reverse_proxy_host_header'), $request->getTrustedHeaderName($request::HEADER_X_FORWARDED_HOST));
+    $this->assertSame($settings->get('reverse_proxy_port_header'), $request->getTrustedHeaderName($request::HEADER_X_FORWARDED_PORT));
     $this->assertSame($settings->get('reverse_proxy_forwarded_header'), $request->getTrustedHeaderName($request::HEADER_FORWARDED));
     $this->assertSame($settings->get('reverse_proxy_addresses'), $request->getTrustedProxies());
   }
diff --git a/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php b/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
index 2eecec9756..f4cd28f18a 100644
--- a/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
+++ b/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
@@ -60,6 +60,12 @@ protected function deprecationEndTest($test, $time) {
    */
   public static function getSkippedDeprecations() {
     return [
+      'Using the unquoted scalar value "!php/object "O:8:\"stdClass\":1:{s:3:\"foo\";s:3:\"bar\";}"" is deprecated since version 3.3 and will be considered as a tagged value in 4.0. You must quote it.',
+      'The Symfony\Component\DependencyInjection\Container::isFrozen() method is deprecated since version 3.3 and will be removed in 4.0. Use the isCompiled() method instead.',
+      'The Symfony\Component\DependencyInjection\DefinitionDecorator class is deprecated since version 3.3 and will be removed in 4.0. Use the Symfony\Component\DependencyInjection\ChildDefinition class instead.',
+      'The Symfony\Component\ClassLoader\ApcClassLoader class is deprecated since version 3.3 and will be removed in 4.0. Use `composer install --apcu-autoloader` instead.',
+      'Using the X-Status-Code header is deprecated since version 3.3 and will be removed in 4.0. Use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent::allowCustomResponseCode() instead.',
+      'The Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher class is deprecated since version 3.3 and will be removed in 4.0. Use EventDispatcher with closure factories instead.',
       'As of 3.1 an Symfony\Component\HttpKernel\Controller\ArgumentResolverInterface is used to resolve arguments. In 4.0 the $argumentResolver becomes the Symfony\Component\HttpKernel\Controller\ArgumentResolver if no other is provided instead of using the $resolver argument.',
       'Symfony\Component\HttpKernel\Controller\ControllerResolver::getArguments is deprecated as of 3.1 and will be removed in 4.0. Implement the Symfony\Component\HttpKernel\Controller\ArgumentResolverInterface and inject it in the HttpKernel instead.',
       'The Twig_Node::getLine method is deprecated since version 1.27 and will be removed in 2.0. Use getTemplateLine() instead.',
diff --git a/sites/default/default.services.yml b/sites/default/default.services.yml
index e1bbbc7e21..dd6d60e54e 100644
--- a/sites/default/default.services.yml
+++ b/sites/default/default.services.yml
@@ -126,15 +126,13 @@ parameters:
   # Not recommended in production environments
   # @default false
   http.response.debug_cacheability_headers: false
-  factory.keyvalue:
-    {}
+  factory.keyvalue: {}
     # Default key/value storage service to use.
     # @default keyvalue.database
     # default: keyvalue.database
     # Collection-specific overrides.
     # state: keyvalue.database
-  factory.keyvalue.expirable:
-    {}
+  factory.keyvalue.expirable: {}
     # Default key/value expirable storage service to use.
     # @default keyvalue.database.expirable
     # default: keyvalue.database.expirable