Video/Screenshare loopback tool.

webrtc/modules/congestion_controller/probe_controller.cc

Index: webrtc/modules/congestion_controller/probe_controller.cc
diff --git a/webrtc/modules/congestion_controller/probe_controller.cc b/webrtc/modules/congestion_controller/probe_controller.cc
index 24ce7d42c376c6ff0c15d25af4cdb122f0ed0ef1..b462072c32b75a087c4b215d5efc93a4aa195b64 100644
--- a/webrtc/modules/congestion_controller/probe_controller.cc
+++ b/webrtc/modules/congestion_controller/probe_controller.cc
@@ -263,6 +263,14 @@ void ProbeController::Process() {
   // Probe bandwidth periodically when in ALR state.
   rtc::Optional<int64_t> alr_start_time =
       pacer_->GetApplicationLimitedRegionStartTime();
+  if (!in_alr && alr_start_time) {
+    in_alr = true;
+    Print("Enter ALR: %ld", *alr_start_time);
+  } else if (in_alr && !alr_start_time) {
+    in_alr = false;
+    Print("Exit ALR");
+  }
+
   if (alr_start_time && estimated_bitrate_bps_ > 0) {
     int64_t next_probe_time_ms =
         std::max(*alr_start_time, time_last_probing_initiated_ms_) +