Avoid unthrown exception warning

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk@1515883 13f79535-47bb-0310-9956-ffa450edef68
Localise @SuppressWarnings

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk@1515885 13f79535-47bb-0310-9956-ffa450edef68