[HttpKernel] Check if "symfony/proxy-manager-bridge" package is installed

Author: hason

src/Symfony/Component/HttpKernel/Kernel.php

@@ -662,7 +662,7 @@ protected function getContainerBuilder()
     {
         $container = new ContainerBuilder(new ParameterBag($this->getKernelParameters()));
 
-        if (class_exists('ProxyManager\Configuration')) {
+        if (class_exists('ProxyManager\Configuration') && class_exists('Symfony\Bridge\ProxyManager\LazyProxy\Instantiator\RuntimeInstantiator')) {
             $container->setProxyInstantiator(new RuntimeInstantiator());
         }
 
@@ -682,7 +682,7 @@ protected function dumpContainer(ConfigCache $cache, ContainerBuilder $container
         // cache the container
         $dumper = new PhpDumper($container);
 
-        if (class_exists('ProxyManager\Configuration')) {
+        if (class_exists('ProxyManager\Configuration') && class_exists('Symfony\Bridge\ProxyManager\LazyProxy\PhpDumper\ProxyDumper')) {
             $dumper->setProxyDumper(new ProxyDumper(md5((string) $cache)));
         }