Relanding "Pass time constant to bwe smoothing filter."

webrtc/modules/congestion_controller/probing_interval_estimator_unittest.cc

 /*
  *  Copyright (c) 2016 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 <memory>
 #include <utility>
 
 #include "webrtc/modules/congestion_controller/probing_interval_estimator.h"
 #include "webrtc/modules/remote_bitrate_estimator/include/mock/mock_aimd_rate_control.h"
 #include "webrtc/test/gmock.h"
 #include "webrtc/test/gtest.h"
 
 using ::testing::Return;
 
 namespace webrtc {
 
 namespace {
 
 constexpr int kMinIntervalMs = 2000;
 constexpr int kMaxIntervalMs = 50000;
+constexpr int kDefaultIntervalMs = 3000;
 
 struct ProbingIntervalEstimatorStates {
   std::unique_ptr<ProbingIntervalEstimator> probing_interval_estimator;
   std::unique_ptr<MockAimdRateControl> aimd_rate_control;
 };
 
 ProbingIntervalEstimatorStates CreateProbingIntervalEstimatorStates() {
   ProbingIntervalEstimatorStates states;
   states.aimd_rate_control.reset(new MockAimdRateControl());
   states.probing_interval_estimator.reset(new ProbingIntervalEstimator(
-      kMinIntervalMs, kMaxIntervalMs, states.aimd_rate_control.get()));
+      kMinIntervalMs, kMaxIntervalMs, kDefaultIntervalMs,
+      states.aimd_rate_control.get()));
   return states;
 }
 }  // namespace
 
-TEST(ProbingIntervalEstimatorTest, NoIntervalUntillWeHaveDrop) {
+TEST(ProbingIntervalEstimatorTest, DefaultIntervalUntillWeHaveDrop) {
   auto states = CreateProbingIntervalEstimatorStates();
 
   EXPECT_CALL(*states.aimd_rate_control, GetLastBitrateDecreaseBps())
       .WillOnce(Return(rtc::Optional<int>()))
       .WillOnce(Return(rtc::Optional<int>(5000)));
   EXPECT_CALL(*states.aimd_rate_control, GetNearMaxIncreaseRateBps())
       .WillOnce(Return(4000))
       .WillOnce(Return(4000));
 
-  EXPECT_EQ(rtc::Optional<int>(),
+  EXPECT_EQ(kDefaultIntervalMs,
             states.probing_interval_estimator->GetIntervalMs());
-  EXPECT_NE(rtc::Optional<int>(),
+  EXPECT_NE(kDefaultIntervalMs,
             states.probing_interval_estimator->GetIntervalMs());
 }
 
 TEST(ProbingIntervalEstimatorTest, CalcInterval) {
   auto states = CreateProbingIntervalEstimatorStates();
   EXPECT_CALL(*states.aimd_rate_control, GetLastBitrateDecreaseBps())
       .WillOnce(Return(rtc::Optional<int>(20000)));
   EXPECT_CALL(*states.aimd_rate_control, GetNearMaxIncreaseRateBps())
       .WillOnce(Return(5000));
-  EXPECT_EQ(rtc::Optional<int>(4000),
-            states.probing_interval_estimator->GetIntervalMs());
+  EXPECT_EQ(4000, states.probing_interval_estimator->GetIntervalMs());
 }
 
 TEST(ProbingIntervalEstimatorTest, IntervalDoesNotExceedMin) {
   auto states = CreateProbingIntervalEstimatorStates();
   EXPECT_CALL(*states.aimd_rate_control, GetLastBitrateDecreaseBps())
       .WillOnce(Return(rtc::Optional<int>(1000)));
   EXPECT_CALL(*states.aimd_rate_control, GetNearMaxIncreaseRateBps())
       .WillOnce(Return(5000));
-  EXPECT_EQ(rtc::Optional<int>(kMinIntervalMs),
-            states.probing_interval_estimator->GetIntervalMs());
+  EXPECT_EQ(kMinIntervalMs, states.probing_interval_estimator->GetIntervalMs());
 }
 
 TEST(ProbingIntervalEstimatorTest, IntervalDoesNotExceedMax) {
   auto states = CreateProbingIntervalEstimatorStates();
   EXPECT_CALL(*states.aimd_rate_control, GetLastBitrateDecreaseBps())
       .WillOnce(Return(rtc::Optional<int>(50000)));
   EXPECT_CALL(*states.aimd_rate_control, GetNearMaxIncreaseRateBps())
       .WillOnce(Return(100));
-  EXPECT_EQ(rtc::Optional<int>(kMaxIntervalMs),
-            states.probing_interval_estimator->GetIntervalMs());
+  EXPECT_EQ(kMaxIntervalMs, states.probing_interval_estimator->GetIntervalMs());
 }
 }  // namespace webrtc