Cast: IPC from browser to renderer to send packet events from transport to cast library.

chrome/browser/media/cast_transport_host_filter.cc

Index: chrome/browser/media/cast_transport_host_filter.cc
diff --git a/chrome/browser/media/cast_transport_host_filter.cc b/chrome/browser/media/cast_transport_host_filter.cc
index 393090f80a2ab8747900aa7f4bc4d19edccd723c..59e113fd3ec578bc1d71fd1693e08249576e2a71 100644
--- a/chrome/browser/media/cast_transport_host_filter.cc
+++ b/chrome/browser/media/cast_transport_host_filter.cc
@@ -8,6 +8,13 @@
 #include "chrome/browser/net/chrome_net_log.h"
 #include "media/cast/transport/cast_transport_sender.h"
 
+namespace {
+
+// How often to send raw events.
+const int kSendRawEventsIntervalSecs = 1;
+
+}
+
 namespace cast {
 
 CastTransportHostFilter::CastTransportHostFilter()
@@ -61,9 +68,17 @@ void CastTransportHostFilter::ReceivedRtpStatistics(
                                  rtp_timestamp));
 }
 
+void CastTransportHostFilter::RawEvents(
+    int32 channel_id,
+    const std::vector<media::cast::PacketEvent>& packet_events) {
+  if (!packet_events.empty())
+    Send(new CastMsg_RawEvents(channel_id, packet_events));
+}
+
 void CastTransportHostFilter::OnNew(
     int32 channel_id,
-    const media::cast::transport::CastTransportConfig& config) {
+    const media::cast::transport::CastTransportConfig& config,
+    const media::cast::CastLoggingConfig& logging_config) {
   media::cast::transport::CastTransportSender* sender =
       id_map_.Lookup(channel_id);
   if (sender) {
@@ -75,9 +90,14 @@ void CastTransportHostFilter::OnNew(
           g_browser_process->net_log(),
           &clock_,
           config,
+          logging_config,
           base::Bind(&CastTransportHostFilter::NotifyStatusChange,
                      base::Unretained(this),

[dcheng, 2014/02/27 22:27:20]

Why is it OK to use base::Unretained(this)? Would be nice to have a comment
above this block. It's not clear to me at all that this is safe.

Similar comments to other uses of base::Unretained(this) in
cast_session_delegate.cc

[imcheng, 2014/02/28 00:15:06]

I did not write this code originally but from looking at the code, the
CastTransportHostFilter owns the sender and doesn't give away ownership. This
callback and the ones below are guaranteed to be only called when the
CastTransportHostFilter still exists. I will add some comment here. I believe it
can be reasoned similarly for CastSessionDelegate.

                      channel_id),
+          base::Bind(&CastTransportHostFilter::RawEvents,
+                     base::Unretained(this),
+                     channel_id),
+          base::TimeDelta::FromSeconds(kSendRawEventsIntervalSecs),
           base::MessageLoopProxy::current());
   sender->SetPacketReceiver(
           base::Bind(&CastTransportHostFilter::ReceivedPacket,