Remove GetFeedbackInterval in sender side BWE.

webrtc/modules/congestion_controller/probe_bitrate_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.
  */
 
@@ skipping 124 matching lines @@
 
 TEST_F(TestProbeBitrateEstimator, IgnoreSizeFirstReceivePacket) {
   AddPacketFeedback(0, 1500, 0, 10);
   AddPacketFeedback(0, 1000, 10, 20);
   AddPacketFeedback(0, 1000, 20, 30);
   AddPacketFeedback(0, 1000, 30, 40);
 
   EXPECT_NEAR(measured_bps_, 800000, 10);
 }
 
+TEST_F(TestProbeBitrateEstimator, NoLastEstimatedBitrateBps) {
+  EXPECT_FALSE(probe_bitrate_estimator_.FetchLastEstimatedBitrateBps());
+}
+
+TEST_F(TestProbeBitrateEstimator, FetchLastEstimatedBitrateBps) {
+  AddPacketFeedback(0, 1000, 0, 10);
+  AddPacketFeedback(0, 1000, 10, 20);
+  AddPacketFeedback(0, 1000, 20, 30);
+  AddPacketFeedback(0, 1000, 30, 40);
+
+  auto estimated_bitrate_bps =
+      probe_bitrate_estimator_.FetchLastEstimatedBitrateBps();
+  EXPECT_TRUE(estimated_bitrate_bps);
+  EXPECT_NEAR(*estimated_bitrate_bps, 800000, 10);
+  EXPECT_FALSE(probe_bitrate_estimator_.FetchLastEstimatedBitrateBps());
+}
+
 }  // namespace webrtc