Rewrite ontimeout-event-override-after-failure for less flakes and better errors

Rewrite ontimeout-event-override-after-failure for less flakes and better errors

This patch rewrites ontimeout-event-override-after-failure with these changes:
1) The test no longer depends on setTimeout racing the network to pass. Instead
of having an async setTimeout check for success, we rely on async callbacks in
xhr's onerror and ontimeout. This should make the test faster in the common case,
and still pass if the test server is slow.
2) The xhr timeout has been increased to 500ms. If this test is flaky due to the
test server not responding fast enough, this change should deflake it.
3) The two failure modes of this test now print different errors which should
help in debugging this if it is still flaky.
4) The test has been reformated to 80cols.

This test is flaky but only very rarely:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=http%2Ftests%2Fxmlhttprequest%2Fontimeout-event-override-after-failure.html

A previous attempt at deflaking this test by increasing the timeout failed:
https://crrev.com/613135a62748f6d2f875f11b9096c368a3873714

After this patch lands, we need to monitor the following:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=http%2Ftests%2Fxmlhttprequest%2Fontimeout-event-override-after-failure.html
If the flakiness disappears, the lines in TestExpectations should be removed.

BUG=464736, 665165
Committed: https://crrev.com/ff4bdcb669f08b5119a63d8eb60c40bb5c4b89c4
Cr-Commit-Position: refs/heads/master@{#434390}

[pdr., 2016-11-22 20:31:19]

pdr@chromium.org changed reviewers:
+ tyoshino@chromium.org, yhirano@chromium.org

[pdr., 2016-11-22 20:32:10]

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

[commit-bot: I haz the power, 2016-11-22 20:32:39]

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

[pdr., 2016-11-22 20:33:50]

pdr vs ontimeout-event-override-after-failure, round 2!

[commit-bot: I haz the power, 2016-11-22 22:10:54]

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

[commit-bot: I haz the power, 2016-11-22 22:10:55]

Dry run: This issue passed the CQ dry run.

[eae, 2016-11-23 22:07:44]

eae@chromium.org changed reviewers:
+ eae@chromium.org

[eae, 2016-11-23 22:07:45]

LGTM

[eae, 2016-11-23 22:07:49]

The CQ bit was checked by eae@chromium.org

[commit-bot: I haz the power, 2016-11-23 22:08:53]

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, 2016-11-24 00:11:28]

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

[commit-bot: I haz the power, 2016-11-24 00:11:29]

Try jobs failed on following builders:
  cast_shell_linux on master.tryserver.chromium.linux (JOB_TIMED_OUT, no build
URL)
  chromeos_x86-generic_chromium_compile_only_ng on
master.tryserver.chromium.linux (JOB_TIMED_OUT, no build URL)
  linux_chromium_chromeos_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  linux_chromium_chromeos_rel_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)
  linux_chromium_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_TIMED_OUT, no build URL)

[pdr., 2016-11-24 00:21:37]

The CQ bit was checked by pdr@chromium.org

[commit-bot: I haz the power, 2016-11-24 00:22:27]

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, 2016-11-24 02:25:00]

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

[commit-bot: I haz the power, 2016-11-24 02:25:01]

Try jobs failed on following builders:
  chromium_presubmit on master.tryserver.chromium.linux (JOB_TIMED_OUT, no build
URL)

[pdr., 2016-11-24 20:10:12]

The CQ bit was checked by pdr@chromium.org

[commit-bot: I haz the power, 2016-11-24 20:10:25]

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, 2016-11-24 21:43:48]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1480018212451550, "parent_rev":
"6904b4871aa5d95e135d89ff7852ecd9cdb7fd4f", "commit_rev":
"a20e33a67962e47d042fa0ce22b4795b7a803c23"}

[commit-bot: I haz the power, 2016-11-24 21:44:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-24 21:46:01]

Description was changed from

==========
Rewrite ontimeout-event-override-after-failure for less flakes and better errors

This patch rewrites ontimeout-event-override-after-failure with these changes:
1) The test no longer depends on setTimeout racing the network to pass. Instead
of having an async setTimeout check for success, we rely on async callbacks in
xhr's onerror and ontimeout. This should make the test faster in the common
case,
and still pass if the test server is slow.
2) The xhr timeout has been increased to 500ms. If this test is flaky due to the
test server not responding fast enough, this change should deflake it.
3) The two failure modes of this test now print different errors which should
help in debugging this if it is still flaky.
4) The test has been reformated to 80cols.

This test is flaky but only very rarely:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=htt...

A previous attempt at deflaking this test by increasing the timeout failed:
https://crrev.com/613135a62748f6d2f875f11b9096c368a3873714

After this patch lands, we need to monitor the following:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=htt...
If the flakiness disappears, the lines in TestExpectations should be removed.

BUG=464736,665165
==========

to

==========
Rewrite ontimeout-event-override-after-failure for less flakes and better errors

This patch rewrites ontimeout-event-override-after-failure with these changes:
1) The test no longer depends on setTimeout racing the network to pass. Instead
of having an async setTimeout check for success, we rely on async callbacks in
xhr's onerror and ontimeout. This should make the test faster in the common
case,
and still pass if the test server is slow.
2) The xhr timeout has been increased to 500ms. If this test is flaky due to the
test server not responding fast enough, this change should deflake it.
3) The two failure modes of this test now print different errors which should
help in debugging this if it is still flaky.
4) The test has been reformated to 80cols.

This test is flaky but only very rarely:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=htt...

A previous attempt at deflaking this test by increasing the timeout failed:
https://crrev.com/613135a62748f6d2f875f11b9096c368a3873714

After this patch lands, we need to monitor the following:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=htt...
If the flakiness disappears, the lines in TestExpectations should be removed.

BUG=464736,665165

Committed: https://crrev.com/ff4bdcb669f08b5119a63d8eb60c40bb5c4b89c4
Cr-Commit-Position: refs/heads/master@{#434390}
==========

[commit-bot: I haz the power, 2016-11-24 21:46:01]

Patchset 1 (id:??) landed as
https://crrev.com/ff4bdcb669f08b5119a63d8eb60c40bb5c4b89c4
Cr-Commit-Position: refs/heads/master@{#434390}