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

webrtc/modules/pacing/alr_detector.h

Index: webrtc/modules/pacing/alr_detector.h
diff --git a/webrtc/modules/pacing/alr_detector.h b/webrtc/modules/pacing/alr_detector.h
index 11eeceaa988a65bdff24308e294902f1eaa23567..688b9453ce101028d084d29aaee13c45fa0c5abc 100644
--- a/webrtc/modules/pacing/alr_detector.h
+++ b/webrtc/modules/pacing/alr_detector.h
@@ -27,7 +27,6 @@ namespace webrtc {
 // AlrDetector provides a signal that can be utilized to adjust
 // estimate bandwidth.
 // Note: This class is not thread-safe.
-
 class AlrDetector {
  public:
   AlrDetector();
@@ -57,8 +56,8 @@ class AlrDetector {
   // kAlrEndUsagePercent. NOTE: This is intentionally conservative at the moment
   // until BW adjustments of application limited region is fine tuned.
   static constexpr int kDefaultAlrBandwidthUsagePercent = 65;
-  static constexpr int kDefaultAlrStartBudgetLevelPercent = 20;
-  static constexpr int kDefaultAlrStopBudgetLevelPercent = -20;
+  static constexpr int kDefaultAlrStartBudgetLevelPercent = 80;
+  static constexpr int kDefaultAlrStopBudgetLevelPercent = 50;
   static const char* kScreenshareProbingBweExperimentName;
 
   void UpdateBudgetWithElapsedTime(int64_t delta_time_ms);
@@ -70,9 +69,26 @@ class AlrDetector {
   int alr_stop_budget_level_percent_;
 
   IntervalBudget alr_budget_;
+  int estimated_bitrate_bps_;
   rtc::Optional<int64_t> alr_started_time_ms_;
 };
 
+class AlrState {

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

Do we really need a class to keep track of whether we are in ALR or not? I'm not
sure I understand the reason for this class.

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

Removed AlrState

+ public:
+  enum class State {
+    kInAlr,
+    kNotInAlr,
+  };
+  AlrState();
+
+  void Update(rtc::Optional<int64_t> alr_start_time_ms);
+  bool HasChangedTo(State state);
+
+ private:
+  bool was_in_alr_;
+  rtc::Optional<State> alr_state_changed_to_;
+};
+
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_PACING_ALR_DETECTOR_H_