Allow packets to be reordered in the fake network pipe.

webrtc/video/video_loopback.cc

Index: webrtc/video/video_loopback.cc
diff --git a/webrtc/video/video_loopback.cc b/webrtc/video/video_loopback.cc
index 2338a84a4399c538dfcf9a24f2983c425d9eaa4a..87aacc6755f86a2f61a785b8435018cf57b98f3e 100644
--- a/webrtc/video/video_loopback.cc
+++ b/webrtc/video/video_loopback.cc
@@ -176,6 +176,8 @@ DEFINE_bool(logs, false, "print logs to stderr");
 
 DEFINE_bool(send_side_bwe, true, "Use send-side bandwidth estimation");
 
+DEFINE_bool(allow_reordering, false, "Allow packet reordering to occur");
+
 DEFINE_string(
     force_fieldtrials,
     "",
@@ -201,6 +203,7 @@ void Loopback() {
   pipe_config.queue_length_packets = flags::QueueSize();
   pipe_config.queue_delay_ms = flags::AvgPropagationDelayMs();
   pipe_config.delay_standard_deviation_ms = flags::StdPropagationDelayMs();
+  pipe_config.allow_reordering = flags::FLAGS_allow_reordering;
 
   Call::Config::BitrateConfig call_bitrate_config;
   call_bitrate_config.min_bitrate_bps = flags::MinBitrateKbps() * 1000;