CustomScheme 对象
scheme字符串 - 自定义的计划,可以被按选项注册。privilegesObject (可选)standardboolean (可选) -默认为falsesecureboolean (可选) - 默认为falsebypassCSPboolean (可选) - 默认为falseallowServiceWorkersboolean (可选) - 默认为falsesupportFetchAPIboolean (可选) - 默认为falsecorsEnabledboolean (可选) - 默认为falsestreamboolean (可选) - 默认为 false.codeCacheboolean (optional) - Enable V8 code cache for the scheme, only works whenstandardis also set to true. Default false.