Add support for GCM cipher suites from RFC 7714.

talk/app/webrtc/peerconnectionfactory.cc

Index: talk/app/webrtc/peerconnectionfactory.cc
diff --git a/talk/app/webrtc/peerconnectionfactory.cc b/talk/app/webrtc/peerconnectionfactory.cc
index ab8fdf5b251a028313a9bb9d11aadcd35dee2407..6b11b98e52a66d886a110ab54221c8d4b2d6686e 100644
--- a/talk/app/webrtc/peerconnectionfactory.cc
+++ b/talk/app/webrtc/peerconnectionfactory.cc
@@ -196,6 +196,7 @@ bool PeerConnectionFactory::Initialize() {
       new cricket::ChannelManager(media_engine, worker_thread_));
 
   channel_manager_->SetVideoRtxEnabled(true);
+  channel_manager_->SetCryptoOptions(options_.crypto_options);
   if (!channel_manager_->Init()) {
     return false;
   }
@@ -206,6 +207,13 @@ bool PeerConnectionFactory::Initialize() {
   return true;
 }
 
+void PeerConnectionFactory::SetOptions(const Options& options) {
+  options_ = options;
+  if (channel_manager_) {
+    channel_manager_->SetCryptoOptions(options.crypto_options);
+  }
+}
+
 rtc::scoped_refptr<AudioSourceInterface>
 PeerConnectionFactory::CreateAudioSource(
     const MediaConstraintsInterface* constraints) {