Update default values for APM stats to match old behavior.

webrtc/modules/audio_processing/include/audio_processing.h

 /*
  *  Copyright (c) 2012 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 490 matching lines @@
     float minimum() const { return minimum_; }
 
    private:
     float instant_ = 0.0f;  // Instantaneous value.
     float average_ = 0.0f;  // Long-term average.
     float maximum_ = 0.0f;  // Long-term maximum.
     float minimum_ = 0.0f;  // Long-term minimum.
   };
 
   struct AudioProcessingStatistics {
+    AudioProcessingStatistics() {
+      residual_echo_return_loss.Set(-100.0f, -100.0f, -100.0f, -100.0f);
+      echo_return_loss.Set(-100.0f, -100.0f, -100.0f, -100.0f);
+      echo_return_loss_enhancement.Set(-100.0f, -100.0f, -100.0f, -100.0f);
+      a_nlp.Set(-100.0f, -100.0f, -100.0f, -100.0f);
+    }
+
     // AEC Statistics.
     // RERL = ERL + ERLE
     Stat residual_echo_return_loss;
     // ERL = 10log_10(P_far / P_echo)
     Stat echo_return_loss;
     // ERLE = 10log_10(P_echo / P_out)
     Stat echo_return_loss_enhancement;
     // (Pre non-linear processing suppression) A_NLP = 10log_10(P_echo / P_a)
     Stat a_nlp;
     // Fraction of time that the AEC linear filter is divergent, in a 1-second
     // non-overlapped aggregation window.
-    float divergent_filter_fraction = 0.0f;
+    float divergent_filter_fraction = -1.0f;
 
     // The delay metrics consists of the delay median and standard deviation. It
     // also consists of the fraction of delay estimates that can make the echo
     // cancellation perform poorly. The values are aggregated until the first
     // call to |GetStatistics()| and afterwards aggregated and updated every
     // second. Note that if there are several clients pulling metrics from
     // |GetStatistics()| during a session the first call from any of them will
     // change to one second aggregation window for all.
-    int delay_median = 0;
-    int delay_standard_deviation = 0;
-    float fraction_poor_delays = 0.0f;
+    int delay_median = -1;
+    int delay_standard_deviation = -1;
+    float fraction_poor_delays = -1.0f;
 
     // Residual echo detector likelihood. This value is not yet calculated and
     // is currently always set to zero.
     // TODO(ivoc): Implement this stat.
-    float residual_echo_likelihood = 0.0f;
+    float residual_echo_likelihood = -1.0f;
   };
 
   // TODO(ivoc): Make this pure virtual when all subclasses have been updated.
   virtual AudioProcessingStatistics GetStatistics() const;
 
   // These provide access to the component interfaces and should never return
   // NULL. The pointers will be valid for the lifetime of the APM instance.
   // The memory for these objects is entirely managed internally.
   virtual EchoCancellation* echo_cancellation() const = 0;
   virtual EchoControlMobile* echo_control_mobile() const = 0;
@@ skipping 516 matching lines @@
   // This does not impact the size of frames passed to |ProcessStream()|.
   virtual int set_frame_size_ms(int size) = 0;
   virtual int frame_size_ms() const = 0;
 
  protected:
   virtual ~VoiceDetection() {}
 };
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_INCLUDE_AUDIO_PROCESSING_H_