Add Cast PLI support on sender side.

chrome/browser/media/cast_transport_host_filter.h

Index: chrome/browser/media/cast_transport_host_filter.h
diff --git a/chrome/browser/media/cast_transport_host_filter.h b/chrome/browser/media/cast_transport_host_filter.h
index 2331e97172d5fa923b8257b5075e467206b1b00b..6b78aa5263a2f6cf4042f10bc7e9f4df1a483436 100644
--- a/chrome/browser/media/cast_transport_host_filter.h
+++ b/chrome/browser/media/cast_transport_host_filter.h
@@ -38,6 +38,9 @@ class CastTransportHostFilter : public content::BrowserMessageFilter {
   void SendCastMessage(int32_t channel_id,
                        uint32_t ssrc,
                        const media::cast::RtcpCastMessage& cast_message);
+  void ReceivedPacket(int32_t channel_id,
+                      scoped_ptr<media::cast::Packet> packet);
+  void SendReceivedPli(int32_t channel_id, uint32_t ssrc);
 
   // BrowserMessageFilter implementation.
   bool OnMessageReceived(const IPC::Message& message) override;