Remove undefined member functions in AlrDetector

Bug: webrtc:11494
Change-Id: I5443931eb194287faf655b2c812d6c4625419a29
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/172925
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Commit-Queue: Ali Tofigh <alito@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31009}

modules/congestion_controller/goog_cc/alr_detector.h

@@ -60,9 +60,6 @@ class AlrDetector {
   // started or empty result if the sender is currently not application-limited.
   absl::optional<int64_t> GetApplicationLimitedRegionStartTime() const;
 
-  void UpdateBudgetWithElapsedTime(int64_t delta_time_ms);
-  void UpdateBudgetWithBytesSent(size_t bytes_sent);
-
  private:
   friend class GoogCcStatePrinter;
   const AlrDetectorConfig conf_;