Use NtpTime in RtcpMeasurement instead of uint sec/uint frac.

webrtc/system_wrappers/include/rtp_to_ntp.h

Index: webrtc/system_wrappers/include/rtp_to_ntp.h
diff --git a/webrtc/system_wrappers/include/rtp_to_ntp.h b/webrtc/system_wrappers/include/rtp_to_ntp.h
index 866144116c89bf39364c56369377a5e2774f01a2..c1e7ab603ec6d15138d1447708cfefac860206d1 100644
--- a/webrtc/system_wrappers/include/rtp_to_ntp.h
+++ b/webrtc/system_wrappers/include/rtp_to_ntp.h
@@ -13,6 +13,7 @@
 
 #include <list>
 
+#include "webrtc/system_wrappers/include/ntp_time.h"
 #include "webrtc/typedefs.h"
 
 namespace webrtc {
@@ -22,8 +23,7 @@ struct RtcpMeasurement {
   RtcpMeasurement(uint32_t ntp_secs, uint32_t ntp_frac, uint32_t timestamp);
   bool IsEqual(const RtcpMeasurement& other) const;
 
-  uint32_t ntp_secs;
-  uint32_t ntp_frac;
+  NtpTime ntp_time;
   uint32_t rtp_timestamp;
 };