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

webrtc/base/openssladapter.cc

Index: webrtc/base/openssladapter.cc
diff --git a/webrtc/base/openssladapter.cc b/webrtc/base/openssladapter.cc
index d3681861860b5591c5fb85e39b47278bfb0c64b7..430191641a72d7f4203a7ce466f23af2055cfb9e 100644
--- a/webrtc/base/openssladapter.cc
+++ b/webrtc/base/openssladapter.cc
@@ -7,6 +7,8 @@
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
+
+#if HAVE_OPENSSL_SSL_H
 
 #include "webrtc/base/openssladapter.h"
 
@@ -963,3 +965,5 @@
 }
 
 } // namespace rtc
+
+#endif  // HAVE_OPENSSL_SSL_H