Mojo EDK: Fix race in named pipe creation for tests

Mojo EDK: Fix race in named pipe creation for tests

This ensures named pipes are created before child process
launch, addressing a potential race where a child can attempt
to connect before a socket/handle is bound to the pipe path by
the server process.

BUG=666356
R=sammc@chromium.org

Committed: https://crrev.com/f39ddac7b3677fc425fc89beba67000b59cbb9ad
Cr-Commit-Position: refs/heads/master@{#433464}

[Ken Rockot(use gerrit already), 2016-11-19 01:30:49]

The CQ bit was checked by rockot@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-19 01:31:16]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Ken Rockot(use gerrit already), 2016-11-19 01:34:09]

The CQ bit was checked by rockot@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-11-19 01:34:30]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Ken Rockot(use gerrit already), 2016-11-19 01:35:06]

Patchset #1 (id:1) has been deleted

[Ken Rockot(use gerrit already), 2016-11-19 01:36:59]

I think this will likely fix the hangs on Android tests. I can repro hangs
locally on every 1 out of ~1000 mojo_system_unittests runs, and they're always
caused by connect failing in the child process on a NAMED_CHILD test instance.
Unsurprisingly, no such repro with this patch applied.

[commit-bot: I haz the power, 2016-11-19 02:32:01]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-19 02:32:02]

Dry run: This issue passed the CQ dry run.

[Sam McNally, 2016-11-20 23:03:49]

lgtm

[Ken Rockot(use gerrit already), 2016-11-20 23:16:57]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2016-11-20 23:17:05]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-21 00:07:13]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1479683817571740,
"parent_rev": ["101abd5dea38141fdd82bd50d15bc263ca7ebcdc", null], "commit_rev":
["a20694e78c2f174d545faafb8968541d23e89cdb", null]}

[commit-bot: I haz the power, 2016-11-21 00:07:38]

Committed patchset #1 (id:20001)

[commit-bot: I haz the power, 2016-11-21 00:09:59]

Description was changed from

==========
Mojo EDK: Fix race in named pipe creation for tests

This ensures named pipes are created before child process
launch, addressing a potential race where a child can attempt
to connect before a socket/handle is bound to the pipe path by
the server process.

BUG=666356
R=sammc@chromium.org
==========

to

==========
Mojo EDK: Fix race in named pipe creation for tests

This ensures named pipes are created before child process
launch, addressing a potential race where a child can attempt
to connect before a socket/handle is bound to the pipe path by
the server process.

BUG=666356
R=sammc@chromium.org

Committed: https://crrev.com/f39ddac7b3677fc425fc89beba67000b59cbb9ad
Cr-Commit-Position: refs/heads/master@{#433464}
==========

[commit-bot: I haz the power, 2016-11-21 00:10:00]

Patchset 1 (id:??) landed as
https://crrev.com/f39ddac7b3677fc425fc89beba67000b59cbb9ad
Cr-Commit-Position: refs/heads/master@{#433464}