Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

vendor/symfony/psr-http-message-bridge/composer.json

@@ -0,0 +1,33 @@
+{
+    "name": "symfony/psr-http-message-bridge",
+    "type": "symfony-bridge",
+    "description": "PSR HTTP message bridge",
+    "keywords": ["http", "psr-7", "http-message"],
+    "homepage": "http://symfony.com",
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Fabien Potencier",
+            "email": "fabien@symfony.com"
+        },
+        {
+            "name": "Symfony Community",
+            "homepage": "http://symfony.com/contributors"
+        }
+    ],
+    "require": {
+        "php": ">=5.3.3",
+        "psr/http-message": "~1.0",
+        "symfony/http-foundation": "~2.3|~3.0"
+    },
+    "require-dev": {
+        "symfony/phpunit-bridge": "~2.7|~3.0"
+    },
+    "suggest": {
+        "zendframework/zend-diactoros": "To use the Zend Diactoros factory"
+    },
+    "autoload": {
+        "psr-4": { "Symfony\\Bridge\\PsrHttpMessage\\": "" }
+    },
+    "minimum-stability": "dev"
+}