Change "hybrid mode" to "|kNack| mode" in comments.

R=stefan@webrtc.org
BUG=none
TEST=none

Review URL: https://webrtc-codereview.appspot.com/56549004

Cr-Commit-Position: refs/heads/master@{#9385}
diff --git a/webrtc/modules/video_coding/main/source/jitter_buffer.cc b/webrtc/modules/video_coding/main/source/jitter_buffer.cc
index 9092a65..da2ca3c 100644
--- a/webrtc/modules/video_coding/main/source/jitter_buffer.cc
+++ b/webrtc/modules/video_coding/main/source/jitter_buffer.cc
@@ -820,7 +820,7 @@
   low_rtt_nack_threshold_ms_ = low_rtt_nack_threshold_ms;
   high_rtt_nack_threshold_ms_ = high_rtt_nack_threshold_ms;
   // Don't set a high start rtt if high_rtt_nack_threshold_ms_ is used, to not
-  // disable NACK in hybrid mode.
+  // disable NACK in |kNack| mode.
   if (rtt_ms_ == kDefaultRtt && high_rtt_nack_threshold_ms_ != -1) {
     rtt_ms_ = 0;
   }
diff --git a/webrtc/modules/video_coding/main/source/jitter_buffer.h b/webrtc/modules/video_coding/main/source/jitter_buffer.h
index 686ec04..d382580 100644
--- a/webrtc/modules/video_coding/main/source/jitter_buffer.h
+++ b/webrtc/modules/video_coding/main/source/jitter_buffer.h
@@ -156,8 +156,8 @@
   void UpdateRtt(int64_t rtt_ms);
 
   // Set the NACK mode. |high_rtt_nack_threshold_ms| is an RTT threshold in ms
-  // above which NACK will be disabled if the NACK mode is |kNackHybrid|, -1
-  // meaning that NACK is always enabled in the hybrid mode.
+  // above which NACK will be disabled if the NACK mode is |kNack|, -1 meaning
+  // that NACK is always enabled in the |kNack| mode.
   // |low_rtt_nack_threshold_ms| is an RTT threshold in ms below which we expect
   // to rely on NACK only, and therefore are using larger buffers to have time
   // to wait for retransmissions.