Update gRPC version to 2022-05-12

Update gRPC to pull in https://github.com/grpc/grpc/pull/28212 to
unblock upgrading libc++ in Chromium.

Bug: 1273285
Change-Id: I1fb483fadc9bd9d1406fbdd22f5b9263e5b6d014
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3644998
Reviewed-by: Yue Li <updowndota@chromium.org>
Reviewed-by: Mirko Bonadei <mbonadei@chromium.org>
Commit-Queue: Alan Zhao <ayzhao@google.com>
Cr-Commit-Position: refs/heads/main@{#1003976}
NOKEYCHECK=True
GitOrigin-RevId: 7c5086062c29c919152a4a0e6e2611f6276a006e
diff --git a/BUILD.gn b/BUILD.gn
index e71d98a..b950726 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -73,6 +73,7 @@
     "//third_party/abseil-cpp/absl/debugging:stacktrace",
     "//third_party/abseil-cpp/absl/debugging:symbolize",
     "//third_party/abseil-cpp/absl/functional:bind_front",
+    "//third_party/abseil-cpp/absl/functional:function_ref",
     "//third_party/abseil-cpp/absl/hash",
     "//third_party/abseil-cpp/absl/memory",
     "//third_party/abseil-cpp/absl/meta:type_traits",