Support finch experiment WebRTC-UDPServerSocketAsync for Windows.

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 fd09f7d30534e890287c0e9ee94c614813199351..2882de91d5b24b68c4cf4c32a6684081e963dd2a 100644
--- a/content/browser/renderer_host/p2p/socket_host_udp.cc
+++ b/content/browser/renderer_host/p2p/socket_host_udp.cc
@@ -68,17 +68,23 @@ P2PSocketHostUdp::PendingPacket::PendingPacket(
 P2PSocketHostUdp::PendingPacket::~PendingPacket() {
 }
 
-P2PSocketHostUdp::P2PSocketHostUdp(IPC::Sender* message_sender,
-                                   int socket_id,
+P2PSocketHostUdp::P2PSocketHostUdp(IPC::Sender* message_sender, int socket_id,

[Sergey Ulanov, 2015/03/26 18:15:32]

Formatting was correct here. One argument per line in function definition. See
https://www.chromium.org/developers/coding-style

[John L. Miller, 2015/03/26 18:23:10]

Done.

                                    P2PMessageThrottler* throttler)
     : P2PSocketHost(message_sender, socket_id, P2PSocketHost::UDP),
-      socket_(
-          new net::UDPServerSocket(GetContentClient()->browser()->GetNetLog(),
-                                   net::NetLog::Source())),
       send_pending_(false),
       last_dscp_(net::DSCP_CS0),
       throttler_(throttler),
       send_buffer_size_(0) {
+  net::UDPServerSocket* socket = new net::UDPServerSocket(
+      GetContentClient()->browser()->GetNetLog(), net::NetLog::Source());
+#if defined(OS_WIN)
+  // If configured for finch experiment, use nonblocking IO.
+  if (base::FieldTrialList::FindFullName("WebRTC-UDPSocketNonBlockingIO") ==
+      "Enabled") {
+    socket->UseNonBlockingIO();
+  }
+#endif
+  socket_.reset(socket);
 }
 
 P2PSocketHostUdp::~P2PSocketHostUdp() {