test: use uv_loop_close and assert its result

uv_loop_delete is considered deprecated.

PR-URL: https://github.com/libuv/libuv/pull/696
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>

test/task.h

@@ -108,10 +108,10 @@ typedef enum {
 /* This macro cleans up the main loop. This is used to avoid valgrind
  * warnings about memory being "leaked" by the main event loop.
  */
-#define MAKE_VALGRIND_HAPPY()           \
-  do {                                  \
-    close_loop(uv_default_loop());      \
-    uv_loop_delete(uv_default_loop());  \
+#define MAKE_VALGRIND_HAPPY()                       \
+  do {                                              \
+    close_loop(uv_default_loop());                  \
+    ASSERT(0 == uv_loop_close(uv_default_loop()));  \
   } while (0)
 
 /* Just sugar for wrapping the main() for a task or helper. */