Don't use async/await for Pool.withResource().

The async gap introduces a potential race condition.

Closes dart-lang/pool#3

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1853273002 .
4 files changed
tree: 119cbb1ea3696ccb9461656c9b5d2d0311cf1301
  1. pkgs/