Add support for GCM cipher suites from RFC 7714.

talk/app/webrtc/peerconnectioninterface.h

Index: talk/app/webrtc/peerconnectioninterface.h
diff --git a/talk/app/webrtc/peerconnectioninterface.h b/talk/app/webrtc/peerconnectioninterface.h
index e449dc4721b67121e250c641f11e2a7830962cc5..eeeb24b6ae9d57e963e70b8a3e9be35b3ce1745f 100644
--- a/talk/app/webrtc/peerconnectioninterface.h
+++ b/talk/app/webrtc/peerconnectioninterface.h
@@ -538,6 +538,9 @@ class PeerConnectionFactoryInterface : public rtc::RefCountInterface {
     // supported by both ends will be used for the connection, i.e. if one
     // party supports DTLS 1.0 and the other DTLS 1.2, DTLS 1.0 will be used.
     rtc::SSLProtocolVersion ssl_max_version;
+
+    // Sets crypto related options, e.g. enabled cipher suites.
+    rtc::CryptoOptions crypto_options;
   };
 
   virtual void SetOptions(const Options& options) = 0;