dcsctp: Add retransmission counters to metrics

Bug: webrtc:15458
Change-Id: Ib90cb0b9a94e1f358685ed319538654b0c8ed5c4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/318581
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Victor Boivie <boivie@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#40683}
diff --git a/net/dcsctp/socket/BUILD.gn b/net/dcsctp/socket/BUILD.gn
index aeb157b..681ddd4 100644
--- a/net/dcsctp/socket/BUILD.gn
+++ b/net/dcsctp/socket/BUILD.gn
@@ -244,6 +244,7 @@
       "../../../test:test_support",
       "../common:handover_testing",
       "../common:internal_types",
+      "../common:math",
       "../packet:chunk",
       "../packet:error_cause",
       "../packet:parameter",