TT#92250 use matching output codec with inject-DTMF

Change-Id: I220947872303c534368363e8f980b94bd7d406a5
(cherry picked from commit 74fd959ccc)

daemon/codec.c

@@ -1007,8 +1007,6 @@ void codec_handlers_update(struct call_media *receiver, struct call_media *sink,
 			// we ignore output codec matches if we must transcode DTMF
 			if (dtmf_pt && !reverse_dtmf_pt)
 				;
-			else if (flags && flags->inject_dtmf)
-				;
 			else
 				dest_codecs = g_hash_table_lookup(sink->codec_names_send, &pt->encoding);
 		}
@@ -1042,6 +1040,13 @@ void codec_handlers_update(struct call_media *receiver, struct call_media *sink,
 				goto transcode;
 			}
 
+			if (flags && flags->inject_dtmf) {
+				// we have a matching output codec, but we were told that we might
+				// want to inject DTMF, so we must still go through our transcoding
+				// engine, despite input and output codecs being the same.
+				goto transcode;
+			}
+
 			// XXX check format parameters as well
 			ilog(LOG_DEBUG, "Sink supports codec " STR_FORMAT, STR_FMT(&pt->encoding_with_params));
 			__make_passthrough_gsl(handler, &passthrough_handlers);