[rtp_rtcp] cleanup in RTCPSender class internals.

webrtc/modules/rtp_rtcp/source/receive_statistics_impl.cc

Index: webrtc/modules/rtp_rtcp/source/receive_statistics_impl.cc
diff --git a/webrtc/modules/rtp_rtcp/source/receive_statistics_impl.cc b/webrtc/modules/rtp_rtcp/source/receive_statistics_impl.cc
index 8ac7e0a38324261286dd5b445824ddcffcd982c0..39efa54eb41a7c06184a0cc51d2b281925287012 100644
--- a/webrtc/modules/rtp_rtcp/source/receive_statistics_impl.cc
+++ b/webrtc/modules/rtp_rtcp/source/receive_statistics_impl.cc
@@ -267,6 +267,7 @@ RtcpStatistics StreamStatisticianImpl::CalculateRtcpStatistics() {
   stats.fraction_lost = local_fraction_lost;
 
   // We need a counter for cumulative loss too.
+  // TODO(danilchap): Ensure cumulative loss is below maximum value of 2^24.
   cumulative_loss_ += missing;
   stats.cumulative_lost = cumulative_loss_;
   stats.extended_max_sequence_number =