Fix BitrateProber to match the requested bitrate more precisely

webrtc/modules/pacing/paced_sender_unittest.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 810 matching lines @@
     send_bucket_->Process();
   }
   int packets_sent = packet_sender.packets_sent();
   // Validate first cluster bitrate. Note that we have to account for number
   // of intervals and hence (packets_sent - 1) on the first cluster.
   EXPECT_NEAR((packets_sent - 1) * kPacketSize * 8000 /
                   (clock_.TimeInMilliseconds() - start),
               kFirstClusterBps, kBitrateProbingError);
   EXPECT_EQ(0, packet_sender.padding_sent());
 
+  clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess());
   start = clock_.TimeInMilliseconds();
   while (packet_sender.packets_sent() < 10) {
     int time_until_process = send_bucket_->TimeUntilNextProcess();
     clock_.AdvanceTimeMilliseconds(time_until_process);
     send_bucket_->Process();
   }
   packets_sent = packet_sender.packets_sent() - packets_sent;
   // Validate second cluster bitrate.
-  EXPECT_NEAR(
-      packets_sent * kPacketSize * 8000 / (clock_.TimeInMilliseconds() - start),
-      kSecondClusterBps, kBitrateProbingError);
+  EXPECT_NEAR((packets_sent - 1) * kPacketSize * 8000 /
+                  (clock_.TimeInMilliseconds() - start),
+              kSecondClusterBps, kBitrateProbingError);
 }
 
 TEST_F(PacedSenderTest, ProbingWithPaddingSupport) {
   const size_t kPacketSize = 1200;
   const int kInitialBitrateBps = 300000;
   uint32_t ssrc = 12346;
   uint16_t sequence_number = 1234;
 
   PacedSenderProbing packet_sender;
   send_bucket_.reset(new PacedSender(&clock_, &packet_sender));
@@ skipping 180 matching lines @@
 
   // No more probing packets.
   EXPECT_CALL(callback_, TimeToSendPadding(_, PacketInfo::kNotAProbe))
         .Times(1)
         .WillRepeatedly(Return(500));
   send_bucket_->Process();
 }
 
 }  // namespace test
 }  // namespace webrtc