Revert of Removing #defines previously used for building without BoringSSL/OpenSSL.

webrtc/base/ssladapter.cc

 /*
  *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/base/ssladapter.h"
 
-#include "webrtc/base/openssladapter.h"
+#include "webrtc/base/sslconfig.h"
+
+#if SSL_USE_OPENSSL
+
+#include "openssladapter.h"
+
+#endif
 
 ///////////////////////////////////////////////////////////////////////////////
 
 namespace rtc {
 
 SSLAdapter*
 SSLAdapter::Create(AsyncSocket* socket) {
+#if SSL_USE_OPENSSL
   return new OpenSSLAdapter(socket);
+#else  // !SSL_USE_OPENSSL
+  delete socket;
+  return NULL;
+#endif  // SSL_USE_OPENSSL
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
+#if SSL_USE_OPENSSL
+
 bool InitializeSSL(VerificationCallback callback) {
   return OpenSSLAdapter::InitializeSSL(callback);
 }
 
 bool InitializeSSLThread() {
   return OpenSSLAdapter::InitializeSSLThread();
 }
 
 bool CleanupSSL() {
   return OpenSSLAdapter::CleanupSSL();
 }
 
+#else  // !SSL_USE_OPENSSL
+
+bool InitializeSSL(VerificationCallback callback) {
+  return true;
+}
+
+bool InitializeSSLThread() {
+  return true;
+}
+
+bool CleanupSSL() {
+  return true;
+}
+
+#endif  // SSL_USE_OPENSSL
+
 ///////////////////////////////////////////////////////////////////////////////
 
 }  // namespace rtc