Reimplemeted "Test and fix for huge bwe drop after alr state"

webrtc/modules/pacing/alr_detector.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 85 matching lines @@
                  << settings.alr_bandwidth_usage_percent
                  << ", ALR end budget level percent: "
                  << settings.alr_start_budget_level_percent
                  << ", ALR end budget level percent: "
                  << settings.alr_stop_budget_level_percent;
   }
 
   return ret;
 }
 
+AlrState::AlrState() : was_in_alr_(false) {}
+
+void AlrState::Update(rtc::Optional<int64_t> alr_start_time_ms) {
+  if (was_in_alr_ && !alr_start_time_ms) {
+    alr_state_changed_to_.emplace(AlrState::State::kNotInAlr);
+  } else if (!was_in_alr_ && alr_start_time_ms) {
+    alr_state_changed_to_.emplace(AlrState::State::kInAlr);
+  } else {
+    alr_state_changed_to_.reset();

[philipel, 2017/07/14 13:56:23]

Isn't |alr_state_changed_to_| just |current_state_|.

[tschumi, 2017/07/14 15:36:51]

Removed AlrState

+  }
+  was_in_alr_ = alr_start_time_ms.has_value();

[philipel, 2017/07/14 13:56:23]

|was_in_alr_| same as |in_alr_|?

[tschumi, 2017/07/14 15:36:51]

Removed AlrState

+}
+
+bool AlrState::HasChangedTo(AlrState::State state) {
+  return alr_state_changed_to_ && *alr_state_changed_to_ == state;
+}
+
 }  // namespace webrtc