[ RUN      ] PrerenderBrowserTest.PageLoadMetricsPrerender
Xlib:  extension "RANDR" missing on display ":99".
[21150:21315:1123/003703.333646:ERROR:bus.cc(395)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
[21150:21150:1123/003703.342492:WARNING:password_store_factory.cc(241)] Using basic (unencrypted) store for password storage. See https://chromium.googlesource.com/chromium/src/+/master/docs/linux_password_storage.md for more information about password storage options.
[21150:21307:1123/003703.451138:ERROR:test_database_manager.cc(64)] Not implemented reached in virtual bool safe_browsing::TestSafeBrowsingDatabaseManager::CheckResourceUrl(const GURL &, safe_browsing::SafeBrowsingDatabaseManager::Client *)
[21150:21348:1123/003703.458883:WARNING:embedded_test_server.cc(228)] Request not handled. Returning 404: /favicon.ico
../../base/test/histogram_tester.cc:72: Failure
      Expected: count
      Which is: 1
To be equal to: 0
Histogram "PageLoad.ParseTiming.NavigationToParseStart" does not exist.
[21150:21150:1123/003704.545892:INFO:chrome_cryptauth_service.cc(222)] Profile is not authenticated yet; waiting before starting CryptAuth managers.
[  FAILED  ] PrerenderBrowserTest.PageLoadMetricsPrerender, where TypeParam =  and GetParam() =  (1829 ms)
[ RUN      ] PrerenderBrowserTest.PageLoadMetricsPrerender
Xlib:  extension "RANDR" missing on display ":99".
[27488:27527:1123/004353.519976:ERROR:bus.cc(395)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
[27488:27488:1123/004353.526188:WARNING:password_store_factory.cc(241)] Using basic (unencrypted) store for password storage. See https://chromium.googlesource.com/chromium/src/+/master/docs/linux_password_storage.md for more information about password storage options.
[27488:27520:1123/004353.628547:ERROR:test_database_manager.cc(64)] Not implemented reached in virtual bool safe_browsing::TestSafeBrowsingDatabaseManager::CheckResourceUrl(const GURL &, safe_browsing::SafeBrowsingDatabaseManager::Client *)
[27488:27554:1123/004353.635604:WARNING:embedded_test_server.cc(228)] Request not handled. Returning 404: /favicon.ico
../../base/test/histogram_tester.cc:72: Failure
      Expected: count
      Which is: 1
To be equal to: 0
Histogram "PageLoad.ParseTiming.NavigationToParseStart" does not exist.
[27488:27488:1123/004354.720601:INFO:chrome_cryptauth_service.cc(222)] Profile is not authenticated yet; waiting before starting CryptAuth managers.
[  FAILED  ] PrerenderBrowserTest.PageLoadMetricsPrerender, where TypeParam =  and GetParam() =  (1807 ms)
[ RUN      ] PrerenderBrowserTest.PageLoadMetricsPrerender
Xlib:  extension "RANDR" missing on display ":99".
[27585:27620:1123/004355.618189:ERROR:bus.cc(395)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
[27585:27585:1123/004355.620193:WARNING:password_store_factory.cc(241)] Using basic (unencrypted) store for password storage. See https://chromium.googlesource.com/chromium/src/+/master/docs/linux_password_storage.md for more information about password storage options.
[27585:27613:1123/004355.733355:ERROR:test_database_manager.cc(64)] Not implemented reached in virtual bool safe_browsing::TestSafeBrowsingDatabaseManager::CheckResourceUrl(const GURL &, safe_browsing::SafeBrowsingDatabaseManager::Client *)
[27585:27645:1123/004355.740607:WARNING:embedded_test_server.cc(228)] Request not handled. Returning 404: /favicon.ico
../../base/test/histogram_tester.cc:72: Failure
      Expected: count
      Which is: 1
To be equal to: 0
Histogram "PageLoad.ParseTiming.NavigationToParseStart" does not exist.
[27585:27585:1123/004356.823159:INFO:chrome_cryptauth_service.cc(222)] Profile is not authenticated yet; waiting before starting CryptAuth managers.
[  FAILED  ] PrerenderBrowserTest.PageLoadMetricsPrerender, where TypeParam =  and GetParam() =  (1815 ms)
[ RUN      ] PrerenderBrowserTest.PageLoadMetricsPrerender
Xlib:  extension "RANDR" missing on display ":99".
[27677:27712:1123/004357.711490:ERROR:bus.cc(395)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
[27677:27677:1123/004357.714780:WARNING:password_store_factory.cc(241)] Using basic (unencrypted) store for password storage. See https://chromium.googlesource.com/chromium/src/+/master/docs/linux_password_storage.md for more information about password storage options.
[27677:27705:1123/004357.817914:ERROR:test_database_manager.cc(64)] Not implemented reached in virtual bool safe_browsing::TestSafeBrowsingDatabaseManager::CheckResourceUrl(const GURL &, safe_browsing::SafeBrowsingDatabaseManager::Client *)
[27677:27738:1123/004357.825420:WARNING:embedded_test_server.cc(228)] Request not handled. Returning 404: /favicon.ico
../../base/test/histogram_tester.cc:72: Failure
      Expected: count
      Which is: 1
To be equal to: 0
Histogram "PageLoad.ParseTiming.NavigationToParseStart" does not exist.
[27677:27677:1123/004358.906030:INFO:chrome_cryptauth_service.cc(222)] Profile is not authenticated yet; waiting before starting CryptAuth managers.
[  FAILED  ] PrerenderBrowserTest.PageLoadMetricsPrerender, where TypeParam =  and GetParam() =  (1799 ms)

Flakiness dashboard: https://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=site_per_process_browser_tests&tests=PrerenderBrowserTest.PageLoadMetricsPrerender

Another example of a flake https://logs.chromium.org/v/?s=chromium%2Fbb%2Fclient.v8.chromium%2FLinux_-_Future%2F12828%2F%2B%2Frecipes%2Fsteps%2Fsite_per_process_browser_tests%2F0%2Flogs%2FPrerenderBrowserTest.PageLoadMetricsPrerender%2F0

sorry future sheriffs - won;t have time to update expectations now.

I'm disabling it for now.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/77ca60a5c8f5592babcb90e0dc349ff3442261c6

commit 77ca60a5c8f5592babcb90e0dc349ff3442261c6
Author: Greg Thompson <grt@chromium.org>
Date: Fri Nov 24 10:13:22 2017

Disable PrerenderBrowserTest.PageLoadMetricsPrerender on Linux due to flakes.

BUG= 788100 
TBR=grt@chromium.org

Change-Id: I8c0699b6af9a8d1502e76e94d9dd7e2d2e703303
Reviewed-on: https://chromium-review.googlesource.com/788379
Reviewed-by: Greg Thompson <grt@chromium.org>
Commit-Queue: Greg Thompson <grt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#519079}
[modify] https://crrev.com/77ca60a5c8f5592babcb90e0dc349ff3442261c6/chrome/browser/prerender/prerender_browsertest.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ac05e5b2d2d9f987d3e38089a5ca436da8360710

commit ac05e5b2d2d9f987d3e38089a5ca436da8360710
Author: Matthew Cary <mattcary@chromium.org>
Date: Thu Nov 30 11:34:41 2017

Prerender: fix flake of PrerenderBrowserTest.PageLoadMetricsPrerender.

Like most of the prerender tests, this test first navigates to a loader
page which makes a prerender request for a second page. This test
examines the page load metrics reported in histograms. The page load
metrics infrastructure may compute events out-of-order, and so buffers
events and emits them in batches. This means that one can not expect
page navigations to be synchronized with page load metrics reporting.

This test was flaking due to this race manifesting between the second
prerendering page load versus the first loader page load. The fix adds a
MetricsWebContentsObserver::TestingObserver in the style of the
PageLoadMetricsWaiter used in page_load_metrics_browsertest.cc.

Bug:  788100 
Change-Id: Ib5d1519597fce5507a8e28f0b153b476f4588c12
Reviewed-on: https://chromium-review.googlesource.com/790392
Reviewed-by: Egor Pasko <pasko@chromium.org>
Commit-Queue: Matthew Cary <mattcary@chromium.org>
Cr-Commit-Position: refs/heads/master@{#520508}
[modify] https://crrev.com/ac05e5b2d2d9f987d3e38089a5ca436da8360710/chrome/browser/prerender/prerender_browsertest.cc

This CL re-enables the test after hopefully fixing the flake.

I'll monitor and close the bug if the flakes have stopped.

It's not flaking any more.

https://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=site_per_process_browser_tests&tests=PageLoadMetricsPrerender