Modified STUN verification functions

The new verification makes verification a function on a message.
It also stores the password used in the request message, so that
it is easily accessible when verifying the response.

Bug: chromium:1177125
Change-Id: I505df4b54214643a28a6b292c4e2262b9d97b097
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/209060
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33366}
diff --git a/test/fuzzers/stun_parser_fuzzer.cc b/test/fuzzers/stun_parser_fuzzer.cc
index 720a699..6ca9eac 100644
--- a/test/fuzzers/stun_parser_fuzzer.cc
+++ b/test/fuzzers/stun_parser_fuzzer.cc
@@ -24,5 +24,6 @@
   std::unique_ptr<cricket::IceMessage> stun_msg(new cricket::IceMessage());
   rtc::ByteBufferReader buf(message, size);
   stun_msg->Read(&buf);
+  stun_msg->ValidateMessageIntegrity("");
 }
 }  // namespace webrtc