The test appears to log a different number of warnings on those bots than elsewhere. Looking...

While I'm building - the tests use two iframes, one at http://localhost:8000/ and one at http://127.0.0.1:8000/ - do we have logic that prevents us from showing the same deprecation warning twice, but since each iframe gets a separate process it's not suppressing?

alexmos@: Do you know about what might be happening with the console warnings here?  (lukasza@ might, but he's OOO.)

Yeah, dropping this into Deprecation::countDeprecation():

DLOG(WARNING) << __FUNCTION__;

With --site-per-process I get:

[127233:127233:0302/103255.273935:8621976599421:WARNING:Deprecation.cpp(148)] countDeprecation
CONSOLE WARNING: line 9: indexedDB.webkitGetDatabaseNames() is deprecated and will be removed in M60, around August 2017. See https://www.chromestatus.com/features/5725741740195840 for more details.
[127249:127249:0302/103255.637004:8621976962468:WARNING:Deprecation.cpp(148)] countDeprecation
CONSOLE WARNING: line 9: indexedDB.webkitGetDatabaseNames() is deprecated and will be removed in M60, around August 2017. See https://www.chromestatus.com/features/5725741740195840 for more details.

Without I get:

[127303:127303:0302/103314.506086:8621995831536:WARNING:Deprecation.cpp(148)] countDeprecation
CONSOLE WARNING: line 9: indexedDB.webkitGetDatabaseNames() is deprecated and will be removed in M60, around August 2017. See https://www.chromestatus.com/features/5725741740195840 for more details.
[127303:127303:0302/103314.526844:8621995852205:WARNING:Deprecation.cpp(148)] countDeprecation

Note that both have two countDeprecation() calls, but in the --site-per-process case they're in different processes (first number in the []) so both actually result in a warning.

The theory from #2 seems very likely.  I don't know the deprecation code at all, but Deprecation::countDeprecation (https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/frame/Deprecation.cpp?l=140) seems to keep track of whether it's recorded the corresponding measurement and logged the message on Page.  The two frames here are in different renderers, with each renderer process having its own Page, and we definitely don't replicate the deprecation state/use counter, hence the two warnings.

I'm not sure what the best thing to do is. I assume this difference in logging is an acceptable behavior change for site-isolation. I don't think we want to change the test. I am unaware of a way to e.g. suppress the deprecation warning for the test. I don't think we have different expectation files (e.g. virtual/XYZ) for site isolation...

Thoughts?

One option would be to call testRunner.setDumpConsoleMessages(false) early in the layout test - this assumes that verifications that are important to the test are covered (or can be covered) in a different way (i.e. by dumping of frame contents / testRunner.dumpAsText).

Ah, perfect - yeah, the tests are basically a try/catch that logs in both branches. Logging is not critical.

https://codereview.chromium.org/2721133006/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/612c5c49898c0766cd07f65f95bc930e98210ef6

commit 612c5c49898c0766cd07f65f95bc930e98210ef6
Author: jsbell <jsbell@chromium.org>
Date: Thu Mar 02 20:28:05 2017

Don't log deprecations in cross-origin iframe Indexed DB tests

Deprecation messages are only logged once per "page". With the
--site-per-process flag set, iframes from different origins reside in
different processes and don't share this information, so more messages
may appear. Suppress the logging in tests where this occurs.

BUG= 697938 

Review-Url: https://codereview.chromium.org/2721133006
Cr-Commit-Position: refs/heads/master@{#454362}

[modify] https://crrev.com/612c5c49898c0766cd07f65f95bc930e98210ef6/third_party/WebKit/LayoutTests/http/tests/security/cross-origin-indexeddb-allowed-expected.txt
[modify] https://crrev.com/612c5c49898c0766cd07f65f95bc930e98210ef6/third_party/WebKit/LayoutTests/http/tests/security/cross-origin-worker-indexeddb-allowed-expected.txt
[modify] https://crrev.com/612c5c49898c0766cd07f65f95bc930e98210ef6/third_party/WebKit/LayoutTests/http/tests/security/resources/cross-origin-iframe-for-indexeddb.html
[modify] https://crrev.com/612c5c49898c0766cd07f65f95bc930e98210ef6/third_party/WebKit/LayoutTests/http/tests/security/resources/cross-origin-iframe-for-worker-indexeddb.html

Thanks all!