Switch from old-style ASSERT macro to new-style ASSERT_EQ,... macros.
Using new-style macros makes it easier to debug test failures
Fixes: https://github.com/libuv/libuv/issues/2974
Pass the loop to MAKE_VALGRIND_HAPPY() so it's explicit on which loop
needs to be cleaned up. Since it asserts on uv_loop_close(), need to
remove a couple of those that were being done before the call.
Cleanup where loop was assigned, so the entire test either uses loop or
uv_default_loop(). Not both.
Also take care of any reqs that may have been left uncleaned.
This changes the prototype of uv_run() from:
int uv_run(uv_loop_t* loop);
To:
int uv_run(uv_loop_t* loop, uv_run_mode mode);
Where `mode` is UV_RUN_DEFAULT, UV_RUN_ONCE or UV_RUN_NOWAIT.
Fixes#683.
