asio: Add dtor to API classes

src/asio_server_request.cc

@@ -36,6 +36,8 @@ namespace server {
 
 request::request() : impl_(make_unique<request_impl>()) {}
 
+request::~request() {}
+
 const header_map &request::header() const { return impl_->header(); }
 
 const std::string &request::method() const { return impl_->method(); }

src/asio_server_response.cc

@@ -36,6 +36,8 @@ namespace server {
 
 response::response() : impl_(make_unique<response_impl>()) {}
 
+response::~response() {}
+
 void response::write_head(unsigned int status_code, header_map h) const {
   impl_->write_head(status_code, std::move(h));
 }

src/includes/nghttp2/asio_http2_server.h

@@ -40,6 +40,7 @@ class request {
 public:
   // Application must not call this directly.
   request();
+  ~request();
 
   // Returns request headers.  The pusedo headers, which start with
   // colon (:), are exluced from this list.
@@ -65,6 +66,7 @@ class response {
 public:
   // Application must not call this directly.
   response();
+  ~response();
 
   // Write response header using |status_code| (e.g., 200) and
   // additional headers in |h|.