Add Cast PLI support on sender side.

media/cast/test/cast_benchmarks.cc

Index: media/cast/test/cast_benchmarks.cc
diff --git a/media/cast/test/cast_benchmarks.cc b/media/cast/test/cast_benchmarks.cc
index 3d3950e5a42c4b70e88ea652fb836dbaa86e527b..14eda7be2173bfcf2348e838226e7ca98e552065 100644
--- a/media/cast/test/cast_benchmarks.cc
+++ b/media/cast/test/cast_benchmarks.cc
@@ -96,16 +96,18 @@ class CastTransportSenderWrapper : public CastTransportSender {
 
   void InitializeAudio(const CastTransportRtpConfig& config,
                        const RtcpCastMessageCallback& cast_message_cb,
-                       const RtcpRttCallback& rtt_cb) final {
+                       const RtcpRttCallback& rtt_cb,
+                       const RtcpPliCallback& key_frame_cb) final {
     audio_ssrc_ = config.ssrc;
-    transport_->InitializeAudio(config, cast_message_cb, rtt_cb);
+    transport_->InitializeAudio(config, cast_message_cb, rtt_cb, key_frame_cb);
   }
 
   void InitializeVideo(const CastTransportRtpConfig& config,
                        const RtcpCastMessageCallback& cast_message_cb,
-                       const RtcpRttCallback& rtt_cb) final {
+                       const RtcpRttCallback& rtt_cb,
+                       const RtcpPliCallback& key_frame_cb) final {
     video_ssrc_ = config.ssrc;
-    transport_->InitializeVideo(config, cast_message_cb, rtt_cb);
+    transport_->InitializeVideo(config, cast_message_cb, rtt_cb, key_frame_cb);
   }
 
   void InsertFrame(uint32_t ssrc, const EncodedFrame& frame) final {