Fix flaky CertificateProviderApiTest.Basic test.

Fix flaky CertificateProviderApiTest.Basic test.

The flakiness was caused by waiting for a wrong number of JavaScript
test results, which resulted in inconsistency between events that were
expected to happen and the events that have actually happened. In a
detailed manner, the reportCertificates callback in file basic.js is
wrapped through chrome.test.callbackPass method, which itself calls
chrome.test.succeed method; meanwhile the C++ code in
certificate_provider_apitest.cc didn't expect this chrome.test.succeed
call, and it behaved as if the
chrome.certificateProvider.onSignDigestRequested event handler was
already executed - which is not always true and causes flakiness.

BUG=576364
Committed: https://crrev.com/7afe71d1455a7224a9bcfcad352c8cc7cec12324
Cr-Commit-Position: refs/heads/master@{#371501}

[emaxx, 2016-01-26 00:38:08]

emaxx@chromium.org changed reviewers:
+ bartfab@chromium.org

[emaxx, 2016-01-26 00:38:09]

Bartosz, PTAL.

[bartfab (slow), 2016-01-26 13:26:22]

lgtm

[emaxx, 2016-01-26 13:29:27]

The CQ bit was checked by emaxx@chromium.org

[commit-bot: I haz the power, 2016-01-26 13:29:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1632053002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1632053002/1

[commit-bot: I haz the power, 2016-01-26 13:34:58]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-01-26 13:36:25]

Description was changed from

==========
Fix flaky CertificateProviderApiTest.Basic test.

The flakiness was caused by waiting for a wrong number of JavaScript
test results, which resulted in inconsistency between events that were
expected to happen and the events that have actually happened. In a
detailed manner, the reportCertificates callback in file basic.js is
wrapped through chrome.test.callbackPass method, which itself calls
chrome.test.succeed method; meanwhile the C++ code in
certificate_provider_apitest.cc didn't expect this chrome.test.succeed
call, and it behaved as if the
chrome.certificateProvider.onSignDigestRequested event handler was
already executed - which is not always true and causes flakiness.

BUG=576364
==========

to

==========
Fix flaky CertificateProviderApiTest.Basic test.

The flakiness was caused by waiting for a wrong number of JavaScript
test results, which resulted in inconsistency between events that were
expected to happen and the events that have actually happened. In a
detailed manner, the reportCertificates callback in file basic.js is
wrapped through chrome.test.callbackPass method, which itself calls
chrome.test.succeed method; meanwhile the C++ code in
certificate_provider_apitest.cc didn't expect this chrome.test.succeed
call, and it behaved as if the
chrome.certificateProvider.onSignDigestRequested event handler was
already executed - which is not always true and causes flakiness.

BUG=576364

Committed: https://crrev.com/7afe71d1455a7224a9bcfcad352c8cc7cec12324
Cr-Commit-Position: refs/heads/master@{#371501}
==========

[commit-bot: I haz the power, 2016-01-26 13:36:26]

Patchset 1 (id:??) landed as
https://crrev.com/7afe71d1455a7224a9bcfcad352c8cc7cec12324
Cr-Commit-Position: refs/heads/master@{#371501}