Cast: Send redundant Cast receiver events through RTCP

We used to send Cast receiver events to the sender through RTCP only
once. That means if the RTCP packet is lost we do not receiver the
event.

This change adds redundancy such that each RTCP packet from Cast
receiver to sender is filled with the last known events. RtcpSender
then remove duplicates. This adds more reliability to the event
collection mechanism in Cast.

Review URL: https://codereview.chromium.org/166623004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252307 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 2 insertions, 12 deletions

diff --git a/media/cast/audio_receiver/audio_receiver.cc b/media/cast/audio_receiver/audio_receiver.cc
index 7dcfe57..48a25f4 100644
--- a/media/cast/audio_receiver/audio_receiver.cc
+++ b/media/cast/audio_receiver/audio_receiver.cc
@@ -17,19 +17,10 @@
 
 namespace {
 
-using media::cast::kMaxIpPacketSize;
-using media::cast::kRtcpCastLogHeaderSize;
-using media::cast::kRtcpReceiverEventLogSize;
-
 // Max time we wait until an audio frame is due to be played out is released.
 static const int64 kMaxAudioFrameWaitMs = 20;
 static const int64 kMinSchedulingDelayMs = 1;
 
-// This is an upper bound on number of events that can fit into a single RTCP
-// packet.
-static const int64 kMaxEventSubscriberEntries =
-    (kMaxIpPacketSize - kRtcpCastLogHeaderSize) / kRtcpReceiverEventLogSize;
-
 }  // namespace
 
 namespace media {
@@ -94,9 +85,8 @@ AudioReceiver::AudioReceiver(scoped_refptr<CastEnvironment> cast_environment,
                              const AudioReceiverConfig& audio_config,
                              transport::PacedPacketSender* const packet_sender)
     : cast_environment_(cast_environment),
-      event_subscriber_(
-          kMaxEventSubscriberEntries,
-          ReceiverRtcpEventSubscriber::kAudioEventSubscriber),
+      event_subscriber_(kReceiverRtcpEventHistorySize,
+                        ReceiverRtcpEventSubscriber::kAudioEventSubscriber),
       codec_(audio_config.codec),
       frequency_(audio_config.frequency),
       audio_buffer_(),