Expose DtlsTransport::remote_ssl_certificates

Bug: chromium:907849
Change-Id: If990d541099edb9a327230e1d78a03b406269885
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/131951
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27558}
diff --git a/api/DEPS b/api/DEPS
index 6afa3d7..34bdfe0 100644
--- a/api/DEPS
+++ b/api/DEPS
@@ -75,6 +75,7 @@
 
   "dtls_transport_interface\.h": [
     "+rtc_base/ref_count.h",
+    "+rtc_base/ssl_certificate.h",
   ],
 
   "dtmf_sender_interface\.h": [