Reland "Use backticks not vertical bars to denote variables in comments for /pc"

Original change's description:
> Revert "Use backticks not vertical bars to denote variables in comments for /pc"
>
> This reverts commit 37ee0f5e594dd772ec6d620b5e5ea8a751b684f0.
>
> Reason for revert: Revert in order to be able to revert https://webrtc-review.googlesource.com/c/src/+/225642
>
> Original change's description:
> > Use backticks not vertical bars to denote variables in comments for /pc
> >
> > Bug: webrtc:12338
> > Change-Id: I88cf10afa5fc810b95d2a585ab2e895dcc163b63
> > Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/226953
> > Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> > Commit-Queue: Artem Titov <titovartem@webrtc.org>
> > Cr-Commit-Position: refs/heads/master@{#34575}
>
> TBR=hta@webrtc.org,titovartem@webrtc.org,webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com
>
> Change-Id: I5eddd3a14e1f664bf831e5c294fbc4de5f6a88af
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: webrtc:12338
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/227082
> Reviewed-by: Björn Terelius <terelius@webrtc.org>
> Commit-Queue: Björn Terelius <terelius@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#34577}

Bug: webrtc:12338
Change-Id: I96bd229b73613c162d11d75fa4f5934e1b4295c7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/227087
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34611}
diff --git a/pc/test/integration_test_helpers.h b/pc/test/integration_test_helpers.h
index af59a83..c7c17b7 100644
--- a/pc/test/integration_test_helpers.h
+++ b/pc/test/integration_test_helpers.h
@@ -799,7 +799,7 @@
       const PeerConnectionInterface::RTCConfiguration* config,
       webrtc::PeerConnectionDependencies dependencies) {
     PeerConnectionInterface::RTCConfiguration modified_config;
-    // If |config| is null, this will result in a default configuration being
+    // If `config` is null, this will result in a default configuration being
     // used.
     if (config) {
       modified_config = *config;
@@ -956,7 +956,7 @@
     }
   }
 
-  // Simulate sending a blob of SDP with delay |signaling_delay_ms_| (0 by
+  // Simulate sending a blob of SDP with delay `signaling_delay_ms_` (0 by
   // default).
   void SendSdpMessage(SdpType type, const std::string& msg) {
     if (signaling_delay_ms_ == 0) {
@@ -977,7 +977,7 @@
     }
   }
 
-  // Simulate trickling an ICE candidate with delay |signaling_delay_ms_| (0 by
+  // Simulate trickling an ICE candidate with delay `signaling_delay_ms_` (0 by
   // default).
   void SendIceMessage(const std::string& sdp_mid,
                       int sdp_mline_index,
@@ -1125,7 +1125,7 @@
   std::string debug_name_;
 
   std::unique_ptr<rtc::FakeNetworkManager> fake_network_manager_;
-  // Reference to the mDNS responder owned by |fake_network_manager_| after set.
+  // Reference to the mDNS responder owned by `fake_network_manager_` after set.
   webrtc::FakeMdnsResponder* mdns_responder_ = nullptr;
 
   rtc::scoped_refptr<webrtc::PeerConnectionInterface> peer_connection_;
@@ -1153,7 +1153,7 @@
   // them, if required.
   std::vector<rtc::scoped_refptr<webrtc::VideoTrackSource>>
       video_track_sources_;
-  // |local_video_renderer_| attached to the first created local video track.
+  // `local_video_renderer_` attached to the first created local video track.
   std::unique_ptr<webrtc::FakeVideoTrackRenderer> local_video_renderer_;
 
   SdpSemantics sdp_semantics_;
@@ -1403,7 +1403,7 @@
                 webrtc::PeerConnectionInterface::kIceConnectionCompleted);
   }
 
-  // When |event_log_factory| is null, the default implementation of the event
+  // When `event_log_factory` is null, the default implementation of the event
   // log factory will be used.
   std::unique_ptr<PeerConnectionIntegrationWrapper> CreatePeerConnectionWrapper(
       const std::string& debug_name,
@@ -1654,8 +1654,8 @@
 
   PeerConnectionIntegrationWrapper* caller() { return caller_.get(); }
 
-  // Set the |caller_| to the |wrapper| passed in and return the
-  // original |caller_|.
+  // Set the `caller_` to the `wrapper` passed in and return the
+  // original `caller_`.
   PeerConnectionIntegrationWrapper* SetCallerPcWrapperAndReturnCurrent(
       PeerConnectionIntegrationWrapper* wrapper) {
     PeerConnectionIntegrationWrapper* old = caller_.release();
@@ -1665,8 +1665,8 @@
 
   PeerConnectionIntegrationWrapper* callee() { return callee_.get(); }
 
-  // Set the |callee_| to the |wrapper| passed in and return the
-  // original |callee_|.
+  // Set the `callee_` to the `wrapper` passed in and return the
+  // original `callee_`.
   PeerConnectionIntegrationWrapper* SetCalleePcWrapperAndReturnCurrent(
       PeerConnectionIntegrationWrapper* wrapper) {
     PeerConnectionIntegrationWrapper* old = callee_.release();
@@ -1687,7 +1687,7 @@
 
   // Expects the provided number of new frames to be received within
   // kMaxWaitForFramesMs. The new expected frames are specified in
-  // |media_expectations|. Returns false if any of the expectations were
+  // `media_expectations`. Returns false if any of the expectations were
   // not met.
   bool ExpectNewFrames(const MediaExpectations& media_expectations) {
     // Make sure there are no bogus tracks confusing the issue.
@@ -1841,11 +1841,11 @@
   SdpSemantics sdp_semantics_;
 
  private:
-  // |ss_| is used by |network_thread_| so it must be destroyed later.
+  // `ss_` is used by `network_thread_` so it must be destroyed later.
   std::unique_ptr<rtc::VirtualSocketServer> ss_;
   std::unique_ptr<rtc::FirewallSocketServer> fss_;
-  // |network_thread_| and |worker_thread_| are used by both
-  // |caller_| and |callee_| so they must be destroyed
+  // `network_thread_` and `worker_thread_` are used by both
+  // `caller_` and `callee_` so they must be destroyed
   // later.
   std::unique_ptr<rtc::Thread> network_thread_;
   std::unique_ptr<rtc::Thread> worker_thread_;