win,shutdown: improve how shutdown is dispatched (libuv#3649)

Split this off from endgame, so that it can be handled separately and
earlier, rather than trying to detect inside endgame which case we are
in. There appear to be some race conditions on the `handle` field still
however, which this does not yet attempt to address.

src/win/internal.h

@@ -88,6 +88,9 @@ void uv__process_tcp_accept_req(uv_loop_t* loop, uv_tcp_t* handle,
     uv_req_t* req);
 void uv__process_tcp_connect_req(uv_loop_t* loop, uv_tcp_t* handle,
     uv_connect_t* req);
+void uv__process_tcp_shutdown_req(uv_loop_t* loop,
+                                  uv_tcp_t* stream,
+                                  uv_shutdown_t* req);
 
 void uv__tcp_close(uv_loop_t* loop, uv_tcp_t* tcp);
 void uv__tcp_endgame(uv_loop_t* loop, uv_tcp_t* handle);
@@ -130,6 +133,7 @@ int uv__pipe_write(uv_loop_t* loop,
                    size_t nbufs,
                    uv_stream_t* send_handle,
                    uv_write_cb cb);
+void uv__pipe_shutdown(uv_loop_t* loop, uv_pipe_t* handle, uv_shutdown_t* req);
 
 void uv__process_pipe_read_req(uv_loop_t* loop, uv_pipe_t* handle,
     uv_req_t* req);
@@ -143,7 +147,6 @@ void uv__process_pipe_shutdown_req(uv_loop_t* loop, uv_pipe_t* handle,
     uv_shutdown_t* req);
 
 void uv__pipe_close(uv_loop_t* loop, uv_pipe_t* handle);
-void uv__pipe_cleanup(uv_loop_t* loop, uv_pipe_t* handle);
 void uv__pipe_endgame(uv_loop_t* loop, uv_pipe_t* handle);
 
 
@@ -177,7 +180,9 @@ void uv__process_tty_accept_req(uv_loop_t* loop, uv_tty_t* handle,
  */
 void uv__process_tty_connect_req(uv_loop_t* loop, uv_tty_t* handle,
     uv_connect_t* req);
-
+void uv__process_tty_shutdown_req(uv_loop_t* loop,
+                                  uv_tty_t* stream,
+                                  uv_shutdown_t* req);
 void uv__tty_endgame(uv_loop_t* loop, uv_tty_t* handle);