Use backticks not vertical bars to denote variables in comments for /modules/audio_coding

Bug: webrtc:12338
Change-Id: I02613d9fca45d00e2477f334b7a0416e7912e26b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/227037
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34621}
diff --git a/modules/audio_coding/neteq/preemptive_expand.h b/modules/audio_coding/neteq/preemptive_expand.h
index e7d2bad..708ebfd 100644
--- a/modules/audio_coding/neteq/preemptive_expand.h
+++ b/modules/audio_coding/neteq/preemptive_expand.h
@@ -37,9 +37,9 @@
         overlap_samples_(overlap_samples) {}
 
   // This method performs the actual PreemptiveExpand operation. The samples are
-  // read from |input|, of length |input_length| elements, and are written to
-  // |output|. The number of samples added through time-stretching is
-  // is provided in the output |length_change_samples|. The method returns
+  // read from `input`, of length `input_length` elements, and are written to
+  // `output`. The number of samples added through time-stretching is
+  // is provided in the output `length_change_samples`. The method returns
   // the outcome of the operation as an enumerator value.
   ReturnCodes Process(const int16_t* pw16_decoded,
                       size_t len,
@@ -48,7 +48,7 @@
                       size_t* length_change_samples);
 
  protected:
-  // Sets the parameters |best_correlation| and |peak_index| to suitable
+  // Sets the parameters `best_correlation` and `peak_index` to suitable
   // values when the signal contains no active speech.
   void SetParametersForPassiveSpeech(size_t input_length,
                                      int16_t* best_correlation,