message: Call Call::GetStats() from the correct thread in VideoSendStreamTest.
  Cr-Commit-Position: refs/heads/master@{#28800}
diff: @@ -1709,7 +1709,9 @@ TEST_F(VideoSendStreamTest, ChangingNetworkRoute) {
  }
  Action OnSendRtp(const uint8_t* packet, size_t length) override {
  - if (call_->GetStats().send_bandwidth_bps > kStartBitrateBps) {
  + Call::Stats stats;
  + task_queue_->SendTask([this, &stats]() { stats = call_->GetStats(); });
  + if (stats.send_bandwidth_bps > kStartBitrateBps) {
  observation_complete_.Set();
  }
  @@ -1834,14 +1836,17 @@ class MaxPaddingSetTest : public test::SendTest {
  static const uint32_t kActualEncodeBitrateBps = 40000;
  static const uint32_t kMinPacketsToSend = 50;
  - explicit MaxPaddingSetTest(bool test_switch_content_type, T* stream_reset_fun)
  + MaxPaddingSetTest(bool test_switch_content_type,
  + T* stream_reset_fun,
  + test::SingleThreadedTaskQueueForTesting* task_queue)
  : SendTest(test::CallTest::kDefaultTimeoutMs),
  call_(nullptr),
  send_stream_(nullptr),
  send_stream_config_(nullptr),
  packets_sent_(0),
  running_without_padding_(test_switch_content_type),
  - stream_resetter_(stream_reset_fun) {
  + stream_resetter_(stream_reset_fun),
  + task_queue_(task_queue) {
  RTC_DCHECK(stream_resetter_);
  }
  @@ -1873,10 +1878,16 @@ class MaxPaddingSetTest : public test::SendTest {
  call_ = sender_call;
  }
  + // Called on the pacer thread.
  Action OnSendRtp(const uint8_t* packet, size_t length) override {
  + // GetStats() needs to be called from the construction thread of call_.
  + Call::Stats stats;
  + task_queue_->SendTask([this, &stats]() { stats = call_->GetStats(); });
  +
  rtc::CritScope lock(&crit_);
  +
  if (running_without_padding_)
  - EXPECT_EQ(0, call_->GetStats().max_padding_bitrate_bps);
  + EXPECT_EQ(0, stats.max_padding_bitrate_bps);
  // Wait until at least kMinPacketsToSend frames have been encoded, so that
  // we have reliable data.
  @@ -1896,7 +1907,7 @@ class MaxPaddingSetTest : public test::SendTest {
  }
  // Make sure the pacer has been configured with a min transmit bitrate.
  - if (call_->GetStats().max_padding_bitrate_bps > 0)
  + if (stats.max_padding_bitrate_bps > 0)
  observation_complete_.Set();
  return SEND_PACKET;
  @@ -1927,12 +1938,13 @@ class MaxPaddingSetTest : public test::SendTest {
  uint32_t packets_sent_ RTC_GUARDED_BY(crit_);
  bool running_without_padding_;
  T* const stream_resetter_;
  + test::SingleThreadedTaskQueueForTesting* task_queue_;
  };
  TEST_F(VideoSendStreamTest, RespectsMinTransmitBitrate) {
  auto reset_fun = [](const VideoSendStream::Config& send_stream_config,
  const VideoEncoderConfig& encoder_config) {};
  - MaxPaddingSetTest<decltype(reset_fun)> test(false, &reset_fun);
  + MaxPaddingSetTest<decltype(reset_fun)> test(false, &reset_fun, &task_queue_);
  RunBaseTest(&test);
  }
  @@ -1950,7 +1962,7 @@ TEST_F(VideoSendStreamTest, RespectsMinTransmitBitrateAfterContentSwitch) {
  Start();
  });
  };
  - MaxPaddingSetTest<decltype(reset_fun)> test(true, &reset_fun);
  + MaxPaddingSetTest<decltype(reset_fun)> test(true, &reset_fun, &task_queue_);
  RunBaseTest(&test);
  }
  