Add offline logging of the system delay for AEC3

Bug: webrtc:8671
Change-Id: I8c1801673d9da05c4c5d5385ad455de4d225fff3
Reviewed-on: https://webrtc-review.googlesource.com/52100
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Commit-Queue: Per Åhgren <peah@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22018}
diff --git a/modules/audio_processing/audio_processing_impl.h b/modules/audio_processing/audio_processing_impl.h
index 8ece029..d0fa8cc 100644
--- a/modules/audio_processing/audio_processing_impl.h
+++ b/modules/audio_processing/audio_processing_impl.h
@@ -31,6 +31,7 @@
 
 namespace webrtc {
 
+class ApmDataDumper;
 class AudioConverter;
 class NonlinearBeamformer;
 
@@ -142,6 +143,9 @@
   struct ApmPublicSubmodules;
   struct ApmPrivateSubmodules;
 
+  std::unique_ptr<ApmDataDumper> data_dumper_;
+  static int instance_count_;
+
   // Submodule interface implementations.
   std::unique_ptr<HighPassFilter> high_pass_filter_impl_;