Enable trendline experiment and bayesian bitrate estimator experiment by default.

webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc

Index: webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
diff --git a/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc b/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
index c87439e5c7d8669ab3b730de3437f73d1a2d10e3..4ce71eee994c945e975f085bb2cb43484019345b 100644
--- a/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
+++ b/webrtc/modules/congestion_controller/delay_based_bwe_unittest_helper.cc
@@ -411,7 +411,7 @@ void DelayBasedBweTest::CapacityDropTestHelper(
   uint32_t bitrate_bps = SteadyStateRun(
       kDefaultSsrc, steady_state_time * kFramerate, kStartBitrate,
       kMinExpectedBitrate, kMaxExpectedBitrate, kInitialCapacityBps);
-  EXPECT_NEAR(kInitialCapacityBps, bitrate_bps, 130000u);
+  EXPECT_NEAR(kInitialCapacityBps, bitrate_bps, 200000u);

[terelius, 2017/03/28 12:18:21]

Do we know why this changes?

[stefan-webrtc, 2017/03/30 08:30:47]

It's needed when combining both trendline and the bayesian estimator. I guess
the bayesian estimator doesn't average out small changes as much as the old
estimator did. Since the uncertainty is based on the difference between the
measurement and the current BWE, it will be fairly certain about smaller
variations. Maybe we should introduce some minimum uncertainty?

   bitrate_observer_.Reset();
 
   // Add an offset to make sure the BWE can handle it.
@@ -492,7 +492,7 @@ void DelayBasedBweTest::TestWrappingHelper(int silence_time_s) {
   clock_.AdvanceTimeMilliseconds(silence_time_s * 1000);
   send_time_ms += silence_time_s * 1000;
 
-  for (size_t i = 0; i < 22; ++i) {
+  for (size_t i = 0; i < 23; ++i) {
     IncomingFeedback(clock_.TimeInMilliseconds(), send_time_ms,
                      sequence_number++, 1000);
     clock_.AdvanceTimeMilliseconds(2 * kFrameIntervalMs);