Use backticks not vertical bars to denote variables in comments

Bug: webrtc:12338
Change-Id: I89c8b3a328d04203177522cbdfd9e606fd4bce4c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/228246
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34696}
diff --git a/api/set_remote_description_observer_interface.h b/api/set_remote_description_observer_interface.h
index 1782555..d1c0753 100644
--- a/api/set_remote_description_observer_interface.h
+++ b/api/set_remote_description_observer_interface.h
@@ -22,7 +22,7 @@
 // operation.
 class SetRemoteDescriptionObserverInterface : public rtc::RefCountInterface {
  public:
-  // On success, |error.ok()| is true.
+  // On success, `error.ok()` is true.
   virtual void OnSetRemoteDescriptionComplete(RTCError error) = 0;
 };