在将我的项目从 Symfony 2.9.X 升级到 Symfony 3.1.X 后，该站点一直在抛出错误：
我目前被这个特定问题难住了，无法解决。
作曲家.json：
{
"name": "jordan/.checkout",
"license": "proprietary",
"type": "project",
"autoload": {
"psr-4": {
"": "src/"
},
"classmap": [
"app/AppKernel.php",
"app/AppCache.php"
]
},
"autoload-dev": {
"psr-4": {
"Tests\\": "tests/"
}
},
"require": {
"php": ">=5.5.9",
"symfony/symfony": "3.1.*",
"doctrine/orm": "^2.5",
"doctrine/doctrine-bundle": "^1.6",
"doctrine/doctrine-cache-bundle": "^1.2",
"symfony/swiftmailer-bundle": "^2.3",
"symfony/monolog-bundle": "^2.8",
"sensio/distribution-bundle": "^5.0",
"sensio/framework-extra-bundle": "^3.0.2",
"incenteev/composer-parameter-handler": "^2.0",
"symfony/assetic-bundle": "^2.8.0"
},
"require-dev": {
"sensio/generator-bundle": "^3.0",
"symfony/phpunit-bridge": "^3.0"
},
"scripts": {
"post-install-cmd": [
"Incenteev\\ParameterHandler\\ScriptHandler::buildParameters",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::prepareDeploymentTarget"
],
"post-update-cmd": [
"Incenteev\\ParameterHandler\\ScriptHandler::buildParameters",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::buildBootstrap",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installRequirementsFile",
"Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::prepareDeploymentTarget"
]
},
"extra": {
"symfony-app-dir": "app",
"symfony-bin-dir": "bin",
"symfony-var-dir": "var",
"symfony-web-dir": "httpdocs",
"symfony-tests-dir": "tests",
"symfony-assets-install": "relative",
"incenteev-parameters": {
"file": "app/config/parameters.yml"
}
}
}