Fix bug where min transmit bitrate wasn't working

webrtc/call/call.cc

Index: webrtc/call/call.cc
diff --git a/webrtc/call/call.cc b/webrtc/call/call.cc
index a6a79789418626dd275556f14bd7616d212fd2f6..7354e4b98b5f0e88c85f6cdb18b97516d8a1498b 100644
--- a/webrtc/call/call.cc
+++ b/webrtc/call/call.cc
@@ -181,6 +181,7 @@ class Call : public webrtc::Call,
   int64_t pacer_bitrate_sum_kbits_ GUARDED_BY(&bitrate_crit_);
   uint32_t min_allocated_send_bitrate_bps_ GUARDED_BY(&bitrate_crit_);
   int64_t num_bitrate_updates_ GUARDED_BY(&bitrate_crit_);
+  int current_min_transmit_bitrate_bps_ GUARDED_BY(&bitrate_crit_);
 
   std::map<std::string, rtc::NetworkRoute> network_routes_;
 
@@ -220,6 +221,8 @@ Call::Call(const Call::Config& config)
       pacer_bitrate_sum_kbits_(0),
       min_allocated_send_bitrate_bps_(0),
       num_bitrate_updates_(0),
+      current_min_transmit_bitrate_bps_(0),
+
       remb_(clock_),
       congestion_controller_(new CongestionController(clock_, this, &remb_)),
       video_send_delay_stats_(new SendDelayStats(clock_)) {
@@ -549,6 +552,10 @@ Call::Stats Call::GetStats() const {
   stats.recv_bandwidth_bps = recv_bandwidth;
   stats.pacer_delay_ms = congestion_controller_->GetPacerQueuingDelayMs();
   stats.rtt_ms = call_stats_->rtcp_rtt_stats()->LastProcessedRtt();
+  {
+    rtc::CritScope cs(&bitrate_crit_);
+    stats.min_transmit_bitrate_bps = current_min_transmit_bitrate_bps_;
+  }
   return stats;
 }
 
@@ -711,6 +718,7 @@ void Call::OnAllocationLimitsChanged(uint32_t min_send_bitrate_bps,
       min_send_bitrate_bps, max_padding_bitrate_bps);
   rtc::CritScope lock(&bitrate_crit_);
   min_allocated_send_bitrate_bps_ = min_send_bitrate_bps;
+  current_min_transmit_bitrate_bps_ = max_padding_bitrate_bps;

[perkj_webrtc, 2016/07/04 07:24:49]

this is the max possible padding bitrate and does not take into account the
current estimate. max_padding_bitrate may be higher than what we actually send.

[sprang_webrtc, 2016/07/04 09:08:47]

Right, good catch.

 }
 
 void Call::ConfigureSync(const std::string& sync_group) {