commit 7f4040902e646228dd515dd52babed87402947a5
author Jonah Williams <jonahwilliams@google.com> Thu Jun 22 10:17:48 2023 -0700
committer dart-internal-monorepo <dart-internal-monorepo@dart-ci-internal.iam.gserviceaccount.com> Thu Jun 22 10:23:53 2023 -0700
tree 1d85bd3145ab8963a008d866d93abed2be181b5f
parent d30675eb24b9f604e827b3c54c325bd6f75bcb86

[Impeller] Add fence waiter trace event. (#43092)

I suspect that some of the worst frame times are caused by submission blocking on adding a fence. Add a trace event that would make that obvious.

![unnamed](https://github.com/flutter/engine/assets/8975114/93650ac8-4451-49d7-b8fa-00fc9f7f4277)
https://dart.googlesource.com/external/github.com/flutter/engine/+/25d857c6f1b6f03e812134a4356890a66dfa6e8c