Add support for GCM cipher suites from RFC 7714.

talk/session/media/channel.h

Index: talk/session/media/channel.h
diff --git a/talk/session/media/channel.h b/talk/session/media/channel.h
index d8fde670a0ec5b714023da1f440faa34254f33c4..1192a5621c20b595615fd3959fde66dd60831719 100644
--- a/talk/session/media/channel.h
+++ b/talk/session/media/channel.h
@@ -174,6 +174,8 @@ class BaseChannel
 
   SrtpFilter* srtp_filter() { return &srtp_filter_; }
 
+  bool SetCryptoOptions(const rtc::CryptoOptions& crypto_options);
+
  protected:
   virtual MediaChannel* media_channel() const { return media_channel_; }
   // Sets the |transport_channel_| (and |rtcp_transport_channel_|, if |rtcp_| is
@@ -294,7 +296,8 @@ class BaseChannel
 
   // Handled in derived classes
   // Get the SRTP crypto suites to use for RTP media
-  virtual void GetSrtpCryptoSuites(std::vector<int>* crypto_suites) const = 0;
+  virtual void GetSrtpCryptoSuites(const rtc::CryptoOptions& crypto_options,
+      std::vector<int>* crypto_suites) const = 0;
   virtual void OnConnectionMonitorUpdate(ConnectionMonitor* monitor,
       const std::vector<ConnectionInfo>& infos) = 0;
 
@@ -332,6 +335,7 @@ class BaseChannel
   bool has_received_packet_;
   bool dtls_keyed_;
   bool secure_required_;
+  rtc::CryptoOptions crypto_options_;
   int rtp_abs_sendtime_extn_id_;
 };
 
@@ -418,7 +422,8 @@ class VoiceChannel : public BaseChannel {
   bool GetStats_w(VoiceMediaInfo* stats);
 
   virtual void OnMessage(rtc::Message* pmsg);
-  virtual void GetSrtpCryptoSuites(std::vector<int>* crypto_suites) const;
+  void GetSrtpCryptoSuites(const rtc::CryptoOptions& crypto_options,
+      std::vector<int>* crypto_suites) const override;
   virtual void OnConnectionMonitorUpdate(
       ConnectionMonitor* monitor, const std::vector<ConnectionInfo>& infos);
   virtual void OnMediaMonitorUpdate(
@@ -504,7 +509,8 @@ class VideoChannel : public BaseChannel {
   bool GetStats_w(VideoMediaInfo* stats);
 
   virtual void OnMessage(rtc::Message* pmsg);
-  virtual void GetSrtpCryptoSuites(std::vector<int>* crypto_suites) const;
+  void GetSrtpCryptoSuites(const rtc::CryptoOptions& crypto_options,
+      std::vector<int>* crypto_suites) const override;
   virtual void OnConnectionMonitorUpdate(
       ConnectionMonitor* monitor, const std::vector<ConnectionInfo>& infos);
   virtual void OnMediaMonitorUpdate(
@@ -621,7 +627,8 @@ class DataChannel : public BaseChannel {
   virtual bool WantsPacket(bool rtcp, rtc::Buffer* packet);
 
   virtual void OnMessage(rtc::Message* pmsg);
-  virtual void GetSrtpCryptoSuites(std::vector<int>* crypto_suites) const;
+  void GetSrtpCryptoSuites(const rtc::CryptoOptions& crypto_options,
+      std::vector<int>* crypto_suites) const override;
   virtual void OnConnectionMonitorUpdate(
       ConnectionMonitor* monitor, const std::vector<ConnectionInfo>& infos);
   virtual void OnMediaMonitorUpdate(