Implement UMA and internal data structure for tracking EWOULDBLOCK.

content/browser/renderer_host/p2p/socket_host_udp.cc

Index: content/browser/renderer_host/p2p/socket_host_udp.cc
diff --git a/content/browser/renderer_host/p2p/socket_host_udp.cc b/content/browser/renderer_host/p2p/socket_host_udp.cc
index 3833b62d03b1b19536896498f75e7ff90ba60f40..ee01ca5ed4c3c8e5a30fa3113f61fab45ddff654 100644
--- a/content/browser/renderer_host/p2p/socket_host_udp.cc
+++ b/content/browser/renderer_host/p2p/socket_host_udp.cc
@@ -75,6 +75,7 @@ P2PSocketHostUdp::P2PSocketHostUdp(IPC::Sender* message_sender,
       send_pending_(false),
       last_dscp_(net::DSCP_CS0),
       throttler_(throttler) {
+  protocol_type_ = P2PSocketHost::UDP;
 }
 
 P2PSocketHostUdp::~P2PSocketHostUdp() {
@@ -211,8 +212,12 @@ void P2PSocketHostUdp::Send(const net::IPEndPoint& to,
     }
   }
 
+  IncrementTotalSentPackets();
+
   if (send_pending_) {
     send_queue_.push_back(PendingPacket(to, data, options, packet_id));
+    IncrementDelayedBytes(data.size());
+    IncrementDelayedPackets();
   } else {
     // TODO(mallinath: Remove unnecessary memcpy in this case.
     PendingPacket packet(to, data, options, packet_id);
@@ -281,8 +286,10 @@ void P2PSocketHostUdp::OnSend(uint64 packet_id, int result) {
 
   // Send next packets if we have them waiting in the buffer.
   while (state_ == STATE_OPEN && !send_queue_.empty() && !send_pending_) {
-    DoSend(send_queue_.front());
+    PendingPacket packet = send_queue_.front();
+    DoSend(packet);
     send_queue_.pop_front();
+    DecrementDelayedBytes(packet.size);
   }
 }