[dart:io] Remove DART_IO_DISABLED

runtime/bin/secure_socket_filter.cc

Index: runtime/bin/secure_socket_filter.cc
diff --git a/runtime/bin/secure_socket_filter.cc b/runtime/bin/secure_socket_filter.cc
index 868d06614b7fc89ac888642045bd09398792e1b9..c6ac6bbe96160f0867845c21b21b9ea3e673dd1f 100644
--- a/runtime/bin/secure_socket_filter.cc
+++ b/runtime/bin/secure_socket_filter.cc
@@ -2,7 +2,7 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-#if !defined(DART_IO_DISABLED) && !defined(DART_IO_SECURE_SOCKET_DISABLED)
+#if !defined(DART_IO_SECURE_SOCKET_DISABLED)
 
 #include "bin/secure_socket_filter.h"
 
@@ -709,5 +709,4 @@ int SSLFilter::ProcessWriteEncryptedBuffer(int start, int end) {
 }  // namespace bin
 }  // namespace dart
 
-#endif  // !defined(DART_IO_DISABLED) &&
-        // !defined(DART_IO_SECURE_SOCKET_DISABLED)
+#endif  // !defined(DART_IO_SECURE_SOCKET_DISABLED)