testConnectTimeout in secure_socket_test.dart & socket_connect_timeout_test.dart not convincing

[brianquinlan]

The test assumes that a timeout exception will result when connecting to the IP 8.8.8.7 and does not inspect the exception details.

Instead, the test could use a C helper program (or Dart FFI) that binds to a socket but does not accept connections to simulate connection timeout.