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

webrtc/base/ssladapter_unittest.cc

Index: webrtc/base/ssladapter_unittest.cc
diff --git a/webrtc/base/ssladapter_unittest.cc b/webrtc/base/ssladapter_unittest.cc
index c591f19658f30d19acfa9a338ccf7ddd2ce59a65..a6ec56ebc0629547f749db5a4c7e475293fbecbf 100644
--- a/webrtc/base/ssladapter_unittest.cc
+++ b/webrtc/base/ssladapter_unittest.cc
@@ -370,6 +370,8 @@
       : SSLAdapterTestBase(rtc::SSL_MODE_DTLS, rtc::KeyParams::ECDSA()) {}
 };
 
+#if SSL_USE_OPENSSL
+
 // Basic tests: TLS
 
 // Test that handshake works, using RSA
@@ -417,3 +419,5 @@
   TestHandshake(true);
   TestTransfer("Hello, world!");
 }
+
+#endif  // SSL_USE_OPENSSL