Persist RTP state for FlexFEC.

webrtc/modules/rtp_rtcp/include/flexfec_sender.h

Index: webrtc/modules/rtp_rtcp/include/flexfec_sender.h
diff --git a/webrtc/modules/rtp_rtcp/include/flexfec_sender.h b/webrtc/modules/rtp_rtcp/include/flexfec_sender.h
index a2c7a4ab1ef7f1d1b9ea1bc3b67b319a3051a5f8..f0ba011b95766604d6e109a78a11245225f3cb00 100644
--- a/webrtc/modules/rtp_rtcp/include/flexfec_sender.h
+++ b/webrtc/modules/rtp_rtcp/include/flexfec_sender.h
@@ -17,10 +17,10 @@
 #include "webrtc/base/array_view.h"
 #include "webrtc/base/basictypes.h"
 #include "webrtc/base/random.h"
-#include "webrtc/base/sequenced_task_checker.h"
 #include "webrtc/config.h"
 #include "webrtc/modules/include/module_common_types.h"
 #include "webrtc/modules/rtp_rtcp/include/flexfec_sender.h"
+#include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h"
 #include "webrtc/modules/rtp_rtcp/source/rtp_header_extension.h"
 #include "webrtc/modules/rtp_rtcp/source/rtp_packet_to_send.h"
 #include "webrtc/modules/rtp_rtcp/source/ulpfec_generator.h"
@@ -40,6 +40,7 @@ class FlexfecSender {
                 uint32_t protected_media_ssrc,
                 const std::vector<RtpExtension>& rtp_header_extensions,
                 rtc::ArrayView<const RtpExtensionSize> extension_sizes,
+                const RtpState* rtp_state,
                 Clock* clock);
   ~FlexfecSender();
 
@@ -64,6 +65,9 @@ class FlexfecSender {
   // Returns the overhead, per packet, for FlexFEC.
   size_t MaxPacketOverhead() const;
 
+  // Only called on the VideoSendStream queue, after operation has shut down.
+  RtpState GetRtpState();
+
  private:
   // Utility.
   Clock* const clock_;