Delete the remaining comments about SrtpTransportInterface.

SrtpTransportInterface has been deleted, but the comment is still
retained.

Bug: None
Change-Id: I5565a29bea663a396560f7458abbe902187b1338
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264660
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Henrik Boström <hbos@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37131}
diff --git a/pc/rtp_transport_internal.h b/pc/rtp_transport_internal.h
index ea1f537..9e81611 100644
--- a/pc/rtp_transport_internal.h
+++ b/pc/rtp_transport_internal.h
@@ -27,10 +27,10 @@
 
 namespace webrtc {
 
-// This represents the internal interface beneath SrtpTransportInterface;
-// it is not accessible to API consumers but is accessible to internal classes
-// in order to send and receive RTP and RTCP packets belonging to a single RTP
-// session. Additional convenience and configuration methods are also provided.
+// This class is an internal interface; it is not accessible to API consumers
+// but is accessible to internal classes in order to send and receive RTP and
+// RTCP packets belonging to a single RTP session. Additional convenience and
+// configuration methods are also provided.
 class RtpTransportInternal : public sigslot::has_slots<> {
  public:
   virtual ~RtpTransportInternal() = default;
diff --git a/pc/srtp_transport.h b/pc/srtp_transport.h
index e4b0d9f..ae62d5b 100644
--- a/pc/srtp_transport.h
+++ b/pc/srtp_transport.h
@@ -41,7 +41,6 @@
 
   virtual ~SrtpTransport() = default;
 
-  // SrtpTransportInterface specific implementation.
   virtual RTCError SetSrtpSendKey(const cricket::CryptoParams& params);
   virtual RTCError SetSrtpReceiveKey(const cricket::CryptoParams& params);