Fix flaky test VideoSendStreamTest.SendsKeepAlive

webrtc/video/video_send_stream_tests.cc

 /*
  *  Copyright (c) 2013 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.
  */
 #include <algorithm>  // max
@@ skipping 3392 matching lines @@
     uint32_t max_bitrate_bps_ GUARDED_BY(&crit_);
     bool first_packet_sent_ GUARDED_BY(&crit_);
     rtc::Event bitrate_changed_event_;
   } test;
 
   RunBaseTest(&test);
 }
 
 TEST_F(VideoSendStreamTest, SendsKeepAlive) {
   const int kTimeoutMs = 50;  // Really short timeout for testing.
-  const int kPayloadType = 20;
 
   class KeepaliveObserver : public test::SendTest {
    public:
     KeepaliveObserver() : SendTest(kDefaultTimeoutMs) {}
 
    private:
     Action OnSendRtp(const uint8_t* packet, size_t length) override {
       RTPHeader header;
       EXPECT_TRUE(parser_->Parse(packet, length, &header));
 
-      if (header.payloadType != kPayloadType) {
+      if (header.payloadType != CallTest::kDefaultKeepalivePayloadType) {
         // The video stream has started. Stop it now.
         if (capturer_)
           capturer_->Stop();
       } else {
         observation_complete_.Set();
       }
 
       return SEND_PACKET;
     }
 
     void ModifyVideoConfigs(
         VideoSendStream::Config* send_config,
         std::vector<VideoReceiveStream::Config>* receive_configs,
         VideoEncoderConfig* encoder_config) override {
       send_config->rtp.keep_alive.timeout_interval_ms = kTimeoutMs;
-      send_config->rtp.keep_alive.payload_type = kPayloadType;
+      send_config->rtp.keep_alive.payload_type =
+          CallTest::kDefaultKeepalivePayloadType;
     }
 
     void PerformTest() override {
       EXPECT_TRUE(Wait()) << "Timed out while waiting for keep-alive packet.";
     }
 
     void OnFrameGeneratorCapturerCreated(
         test::FrameGeneratorCapturer* frame_generator_capturer) override {
       capturer_ = frame_generator_capturer;
     }
 
     test::FrameGeneratorCapturer* capturer_ = nullptr;
   } test;
 
   RunBaseTest(&test);
 }
 
 }  // namespace webrtc