Add periodic logging of number of captured and dropped frames in VideoCaptureInput.

webrtc/video/vie_encoder.h

Index: webrtc/video/vie_encoder.h
diff --git a/webrtc/video/vie_encoder.h b/webrtc/video/vie_encoder.h
index dd74b20409e7679ec4fa03d25a6165ce587f0618..1b524e5bb9ecd730e8c4c343da7b208c3a1e97f4 100644
--- a/webrtc/video/vie_encoder.h
+++ b/webrtc/video/vie_encoder.h
@@ -153,6 +153,10 @@ class ViEEncoder : public VideoCaptureInput,
   // Delta used for translating between NTP and internal timestamps.
   const int64_t delta_ntp_internal_ms_;
 
+  int64_t last_frame_log_ms_ GUARDED_BY(incoming_frame_race_checker_);
+  int captured_frame_count_ ACCESS_ON(&encoder_queue_);
+  int dropped_frame_count_ ACCESS_ON(&encoder_queue_);
+
   // All public methods are proxied to |encoder_queue_|. It must must be
   // destroyed first to make sure no tasks are run that use other members.
   rtc::TaskQueue encoder_queue_;