Use TaskScheduler instead of PostTask in P2PSocketDispatcherHost.

content/browser/renderer_host/p2p/socket_dispatcher_host.h

Index: content/browser/renderer_host/p2p/socket_dispatcher_host.h
diff --git a/content/browser/renderer_host/p2p/socket_dispatcher_host.h b/content/browser/renderer_host/p2p/socket_dispatcher_host.h
index 59b69a93fc838d251517ef0bd72523b5a2b79a7a..be6b2d78e6d37e38f763b72727cd7b70566d4858 100644
--- a/content/browser/renderer_host/p2p/socket_dispatcher_host.h
+++ b/content/browser/renderer_host/p2p/socket_dispatcher_host.h
@@ -14,6 +14,7 @@
 #include <vector>
 
 #include "base/macros.h"
+#include "base/sequenced_task_runner.h"
 #include "content/browser/renderer_host/p2p/socket_host_throttler.h"
 #include "content/common/p2p_socket_type.h"
 #include "content/public/browser/browser_message_filter.h"
@@ -126,6 +127,10 @@ class P2PSocketDispatcherHost
   bool dump_outgoing_rtp_packet_;
   RenderProcessHost::WebRtcRtpPacketCallback packet_callback_;
 
+  // Used to call DoGetNetworkList, which may briefly block since getting the
+  // default local address involves creating a dummy socket.
+  const scoped_refptr<base::SequencedTaskRunner> network_list_task_runner_;
+
   DISALLOW_COPY_AND_ASSIGN(P2PSocketDispatcherHost);
 };