Only use payload size within the receive/send interval for bitrate probing.

webrtc/modules/congestion_controller/probe_bitrate_estimator_unittest.cc

Index: webrtc/modules/congestion_controller/probe_bitrate_estimator_unittest.cc
diff --git a/webrtc/modules/congestion_controller/probe_bitrate_estimator_unittest.cc b/webrtc/modules/congestion_controller/probe_bitrate_estimator_unittest.cc
index e3bbd5a22793e2d8a73c0a277ae02f9fc036acb9..128f1bdb1364a40c396ca122ee5083cd0cf159d2 100644
--- a/webrtc/modules/congestion_controller/probe_bitrate_estimator_unittest.cc
+++ b/webrtc/modules/congestion_controller/probe_bitrate_estimator_unittest.cc
@@ -125,4 +125,17 @@ TEST_F(TestProbeBitrateEstimator, OldProbe) {
   EXPECT_EQ(1ul, results_.size());
 }
 
+// Requesting to sending padding can result in multiple packets being sent, but
+// all with the same timestamp.
+TEST_F(TestProbeBitrateEstimator, MultiplePaddingPackets) {
+  AddPacketFeedback(0, 1000, 0, 10);
+  AddPacketFeedback(0, 1000, 10, 40);
+  AddPacketFeedback(0, 200, 10, 43);
+  AddPacketFeedback(0, 1000, 20, 70);
+  AddPacketFeedback(0, 220, 20, 74);
+  AddPacketFeedback(0, 1000, 30, 85);
+
+  CheckResult(0, 353600, 10, 85);
+}
+
 }  // namespace webrtc