Fix failure in xctest runner because the io_thread_task_runner_
was assigned too late. In the test runners a
base::SingleThreadTaskExecutor is created and a watcher is
immediately added. This was failing because the DoRun did not
execute yet. Pump Attach for the MessagePumpIOIOSLibDispatch
class so we can know when the task runner is available.
Bug: 40254930
Change-Id: Ib0b09f7b7681d4e0fe30137828b116e7cbc8aaee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6270218
Reviewed-by: Gabriel Charette <gab@chromium.org>
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1420744}
7b8c941754