Add support for GCM cipher suites from RFC 7714.

talk/session/media/channelmanager.cc

Index: talk/session/media/channelmanager.cc
diff --git a/talk/session/media/channelmanager.cc b/talk/session/media/channelmanager.cc
index e7a4b8bddb99e56c561a51b218d8fc74e311d200..ba24a242558be91756fe9d82c8c401956832984b 100644
--- a/talk/session/media/channelmanager.cc
+++ b/talk/session/media/channelmanager.cc
@@ -106,6 +106,7 @@ void ChannelManager::Construct(MediaEngineInterface* me,
   local_renderer_ = NULL;
   capturing_ = false;
   enable_rtx_ = false;
+  enable_gcm_crypto_suites_ = false;
 
   capture_manager_->SignalCapturerStateChange.connect(
       this, &ChannelManager::OnVideoCaptureStateChange);
@@ -142,6 +143,11 @@ bool ChannelManager::SetVideoRtxEnabled(bool enable) {
   }
 }
 
+bool ChannelManager::SetEnableGcmCryptoSuites(bool enable) {
+  enable_gcm_crypto_suites_ = enable;
+  return true;
+}
+
 void ChannelManager::GetSupportedAudioCodecs(
     std::vector<AudioCodec>* codecs) const {
   codecs->clear();
@@ -275,6 +281,7 @@ VoiceChannel* ChannelManager::CreateVoiceChannel_w(
   VoiceChannel* voice_channel =
       new VoiceChannel(worker_thread_, media_engine_.get(), media_channel,
                        transport_controller, content_name, rtcp);
+  voice_channel->SetEnableGcmCryptoSuites(enable_gcm_crypto_suites_);
   if (!voice_channel->Init()) {
     delete voice_channel;
     return nullptr;
@@ -333,6 +340,7 @@ VideoChannel* ChannelManager::CreateVideoChannel_w(
 
   VideoChannel* video_channel = new VideoChannel(
       worker_thread_, media_channel, transport_controller, content_name, rtcp);
+  video_channel->SetEnableGcmCryptoSuites(enable_gcm_crypto_suites_);
   if (!video_channel->Init()) {
     delete video_channel;
     return NULL;
@@ -391,6 +399,7 @@ DataChannel* ChannelManager::CreateDataChannel_w(
 
   DataChannel* data_channel = new DataChannel(
       worker_thread_, media_channel, transport_controller, content_name, rtcp);
+  data_channel->SetEnableGcmCryptoSuites(enable_gcm_crypto_suites_);
   if (!data_channel->Init()) {
     LOG(LS_WARNING) << "Failed to init data channel.";
     delete data_channel;