Re-add RemoteBitrateEstimator::GetStats.

webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h

Index: webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h
diff --git a/webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h b/webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h
index c815ee0cfc8d46fc926204405ff5623c232ab56b..21865308aa08b884ce9b2d3dce9083c98bdfb892 100644
--- a/webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h
+++ b/webrtc/modules/remote_bitrate_estimator/include/remote_bitrate_estimator.h
@@ -38,6 +38,9 @@ class RemoteBitrateObserver {
   virtual ~RemoteBitrateObserver() {}
 };
 
+// TODO(holmer): Remove when all implementations have been updated.
+struct ReceiveBandwidthEstimatorStats {};
+
 class RemoteBitrateEstimator : public CallStatsObserver, public Module {
  public:
   static const int kDefaultMinBitrateBps = 30000;
@@ -67,6 +70,11 @@ class RemoteBitrateEstimator : public CallStatsObserver, public Module {
   virtual bool LatestEstimate(std::vector<uint32_t>* ssrcs,
                               uint32_t* bitrate_bps) const = 0;
 
+  // TODO(holmer): Remove when all implementations have been updated.
+  bool GetStats(ReceiveBandwidthEstimatorStats* output) const {
+    return false;
+  }
+
   virtual void SetMinBitrate(int min_bitrate_bps) = 0;
 
  protected: