Set up for mac native secure sockets

runtime/bin/secure_socket_boringssl.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // 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.
 
+#include "platform/globals.h"
+#if defined(TARGET_OS_ANDROID) || \
+    defined(TARGET_OS_LINUX)   || \
+    defined(TARGET_OS_WINDOWS)
+
 #include "bin/secure_socket.h"
+#include "bin/secure_socket_boringssl.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <stdio.h>
 #include <string.h>
 
 #include <openssl/bio.h>
 #include <openssl/err.h>
 #include <openssl/pkcs12.h>
@@ skipping 741 matching lines @@
   {
     ScopedMemBIO bio(ThrowIfError(Dart_GetNativeArgument(args, 1)));
     status = SetTrustedCertificatesBytes(context, bio.bio(), password);
   }
   CheckStatus(status,
               "TlsException",
               "Failure in setTrustedCertificatesBytes");
 }
 
 
+void FUNCTION_NAME(SecurityContext_AlpnSupported)(Dart_NativeArguments args) {
+  Dart_SetReturnValue(args, Dart_NewBoolean(true));
+}
+
+
 void FUNCTION_NAME(SecurityContext_TrustBuiltinRoots)(
     Dart_NativeArguments args) {
   SSL_CTX* context = GetSecurityContext(args);
   X509_STORE* store = SSL_CTX_get_cert_store(context);
   BIO* roots_bio =
       BIO_new_mem_buf(const_cast<unsigned char*>(root_certificates_pem),
                       root_certificates_pem_length);
   X509* root_cert;
   // PEM_read_bio_X509 reads PEM-encoded certificates from a bio (in our case,
   // backed by a memory buffer), and returns X509 objects, one by one.
@@ skipping 874 matching lines @@
     } else {
       if (SSL_LOG_DATA) Log::Print(
           "WriteEncrypted  BIO_read wrote %d bytes\n", bytes_processed);
     }
   }
   return bytes_processed;
 }
 
 }  // namespace bin
 }  // namespace dart
+
+#endif  // defined(TARGET_OS_LINUX)