Findit identified the culprit r563370 with confidence 100.0% in the config "chromium.chromiumos / linux-chromeos-rel"
based on the flakiness trend:

https://findit-for-me.appspot.com/waterfall/flake?key=ag9zfmZpbmRpdC1mb3ItbWVyvgELEhdNYXN0ZXJGbGFrZUFuYWx5c2lzUm9vdCKHAWNocm9taXVtLmNocm9taXVtb3MvbGludXgtY2hyb21lb3MtcmVsLzg3ODQvbWFzaF9icm93c2VyX3Rlc3RzL1VHRm5aVXh2WVdSRFlYQndhVzVuUW5KdmQzTmxjbFJsYzNRdVVHRm5aVXh2WVdSRFlYQndhVzVuUW14dlkydHpURzloWkhNPQwLEhNNYXN0ZXJGbGFrZUFuYWx5c2lzGAEM


Automatically posted by the findit-for-me app (https://goo.gl/Ot9f7N).
Feedback is welcome! Please use component Tools>Test>FindIt>Flakiness

Detected 4 new flakes for test/step "PageLoadCappingBrowserTest.PageLoadCappingBlocksLoads". To see the actual flakes, please visit https://chromium-try-flakes.appspot.com/all_flake_occurrences?key=ahVzfmNocm9taXVtLXRyeS1mbGFrZXNyQAsSBUZsYWtlIjVQYWdlTG9hZENhcHBpbmdCcm93c2VyVGVzdC5QYWdlTG9hZENhcHBpbmdCbG9ja3NMb2Fkcww. This message was posted automatically by the chromium-try-flakes app. Since flakiness is ongoing, the issue was moved back into Sheriff Bug Queue (unless already there).

Failure looks related to the test running in specific configurations. If anyone needs to disable this before I do. Feel free to disable the flaky tests and I will investigate on Monday.

This flakes extremely heavily on linux-chromeos-rel and linux-chromeos-dbg, but also on Linux Tests, Linux ASan LSan Tests (1), Linux Chromium OS ASan LSan Tests (1), Linux ChromiumOS MSan Tests, Win 7 Tests x64 (1), Win7 (32) Tests, Win7 Tests (1), Win7 Tests (dbg)(1)

PageLoadCappingBrowserTest.PageLoadCappingBlocksLoadsAndResume is also flaky on Lsan and Asan on Linux.

[ RUN      ] PageLoadCappingBrowserTest.PageLoadCappingBlocksLoadsAndResume
Xlib:  extension "RANDR" missing on display ":99".
[22708:22846:0603/045005.142874:ERROR:bus.cc(394)] Failed to connect to the bus: Could not parse server address: Unknown address type (examples of valid types are "tcp" and on UNIX "unix")
[22708:22708:0603/045005.231177:WARNING:password_store_factory.cc(250)] 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.

(browser_tests:22708): LIBDBUSMENU-GLIB-WARNING **: Unable to get session bus: Unknown or unsupported transport 'disabled' for address 'disabled:'
[22708:22708:0603/045006.162206:WARNING:gaia_auth_fetcher.cc(902)] Could not reach Google Accounts servers: errno -11
[22708:22708:0603/045007.004319:WARNING:gaia_auth_fetcher.cc(902)] Could not reach Google Accounts servers: errno -11
[22708:22929:0603/045007.375244:WARNING:embedded_test_server.cc(229)] Request not handled. Returning 404: /favicon.ico
[22708:22929:0603/045007.604018:WARNING:embedded_test_server.cc(229)] Request not handled. Returning 404: /image0.png
[22708:22929:0603/045007.683989:WARNING:embedded_test_server.cc(229)] Request not handled. Returning 404: /image1.png
=================================================================
==22708==ERROR: AddressSanitizer: stack-use-after-scope on address 0x7f4c9e05da30 at pc 0x0000154e8123 bp 0x7f4c71797e30 sp 0x7f4c71797e28
READ of size 8 at 0x7f4c9e05da30 thread T30 (EmbeddedTestSer)
[22708:22708:0603/045009.993707:WARNING:gaia_auth_fetcher.cc(902)] Could not reach Google Accounts servers: errno -11
    #0 0x154e8122 in net::test_server::EmbeddedTestServer::HandleReadResult(net::test_server::HttpConnection*, int) net/test/embedded_test_server/embedded_test_server.cc:436:27
    #1 0x154e79a0 in net::test_server::EmbeddedTestServer::ReadData(net::test_server::HttpConnection*) net/test/embedded_test_server/embedded_test_server.cc:422:10
    #2 0x1729b48e in Run base/callback.h:96:12
    #3 0x1729b48e in net::SSLServerContextImpl::SocketImpl::DoHandshakeCallback(int) net/socket/ssl_server_socket_impl.cc:688
    #4 0x16cef0b7 in net::SocketBIOAdapter::OnSocketReadIfReadyComplete(int) net/socket/socket_bio_adapter.cc:203:14
    #5 0x16cf2d45 in Invoke<void (net::SocketBIOAdapter::*)(int), const base::WeakPtr<net::SocketBIOAdapter> &, int> base/bind_internal.h:507:12
    #6 0x16cf2d45 in MakeItSo<void (net::SocketBIOAdapter::*const &)(int), const base::WeakPtr<net::SocketBIOAdapter> &, int> base/bind_internal.h:627
    #7 0x16cf2d45 in RunImpl<void (net::SocketBIOAdapter::*const &)(int), const std::__1::tuple<base::WeakPtr<net::SocketBIOAdapter> > &, 0> base/bind_internal.h:681
    #8 0x16cf2d45 in base::internal::Invoker<base::internal::BindState<void (net::SocketBIOAdapter::*)(int), base::WeakPtr<net::SocketBIOAdapter> >, void (int)>::Run(base::internal::BindStateBase*, int) base/bind_internal.h:663
    #9 0x172a2cb9 in Run base/callback.h:96:12
    #10 0x172a2cb9 in net::TCPClientSocket::DidCompleteReadWrite(base::OnceCallback<void (int)>, int) net/socket/tcp_client_socket.cc:383
    #11 0x172a0153 in net::TCPClientSocket::DidCompleteRead(base::OnceCallback<void (int)>, int) net/socket/tcp_client_socket.cc:371:3
    #12 0x172a2eb5 in Invoke<void (net::TCPClientSocket::*)(base::OnceCallback<void (int)>, int), net::TCPClientSocket *, base::OnceCallback<void (int)>, int> base/bind_internal.h:507:12
    #13 0x172a2eb5 in MakeItSo<void (net::TCPClientSocket::*)(base::OnceCallback<void (int)>, int), net::TCPClientSocket *, base::OnceCallback<void (int)>, int> base/bind_internal.h:607
    #14 0x172a2eb5 in RunImpl<void (net::TCPClientSocket::*)(base::OnceCallback<void (int)>, int), std::__1::tuple<base::internal::UnretainedWrapper<net::TCPClientSocket>, base::OnceCallback<void (int)> >, 0, 1> base/bind_internal.h:681
    #15 0x172a2eb5 in base::internal::Invoker<base::internal::BindState<void (net::TCPClientSocket::*)(base::OnceCallback<void (int)>, int), base::internal::UnretainedWrapper<net::TCPClientSocket>, base::OnceCallback<void (int)> >, void (int)>::RunOnce(base::internal::BindStateBase*, int) base/bind_internal.h:649
    #16 0x1773ecde in Run base/callback.h:96:12
    #17 0x1773ecde in net::TCPSocketPosix::ReadIfReadyCompleted(base::OnceCallback<void (int)>, int) net/socket/tcp_socket_posix.cc:710
    #18 0x177444e5 in Invoke<void (net::TCPSocketPosix::*)(base::OnceCallback<void (int)>, int), net::TCPSocketPosix *, base::OnceCallback<void (int)>, int> base/bind_internal.h:507:12
    #19 0x177444e5 in MakeItSo<void (net::TCPSocketPosix::*)(base::OnceCallback<void (int)>, int), net::TCPSocketPosix *, base::OnceCallback<void (int)>, int> base/bind_internal.h:607
    #20 0x177444e5 in RunImpl<void (net::TCPSocketPosix::*)(base::OnceCallback<void (int)>, int), std::__1::tuple<base::internal::UnretainedWrapper<net::TCPSocketPosix>, base::OnceCallback<void (int)> >, 0, 1> base/bind_internal.h:681
    #21 0x177444e5 in base::internal::Invoker<base::internal::BindState<void (net::TCPSocketPosix::*)(base::OnceCallback<void (int)>, int), base::internal::UnretainedWrapper<net::TCPSocketPosix>, base::OnceCallback<void (int)> >, void (int)>::RunOnce(base::internal::BindStateBase*, int) base/bind_internal.h:649
    #22 0x1774d500 in Run base/callback.h:96:12
    #23 0x1774d500 in net::SocketPosix::ReadCompleted() net/socket/socket_posix.cc:560
    #24 0x1774cb65 in net::SocketPosix::OnFileCanReadWithoutBlocking(int) net/socket/socket_posix.cc:464:5
    #25 0x154bdc5c in base::MessagePumpLibevent::OnLibeventNotification(int, short, void*) base/message_loop/message_pump_libevent.cc
    #26 0x18474e28 in event_process_active base/third_party/libevent/event.c:381:4
    #27 0x18474e28 in event_base_loop base/third_party/libevent/event.c:521
    #28 0x154be401 in base::MessagePumpLibevent::Run(base::MessagePump::Delegate*) base/message_loop/message_pump_libevent.cc:214:5
    #29 0x15268b61 in base::MessageLoop::Run(bool) base/message_loop/message_loop.cc:271:12
    #30 0x15312aba in base::RunLoop::Run() base/run_loop.cc:102:14
    #31 0x153c4114 in base::Thread::Run(base::RunLoop*) base/threading/thread.cc:255:13
    #32 0x153c4adf in base::Thread::ThreadMain() base/threading/thread.cc:337:3
    #33 0x154ace62 in base::(anonymous namespace)::ThreadFunc(void*) base/threading/platform_thread_posix.cc:76:13
    #34 0x7f4cac67c183 in start_thread /build/eglibc-ripdx6/eglibc-2.19/nptl/pthread_create.c:312

Address 0x7f4c9e05da30 is located in stack of thread T0 (browser_tests) at offset 560 in frame
    #0 0x88acaaf in PageLoadCappingBrowserTest_PageLoadCappingBlocksLoadsAndResume_Test::RunTestOnMainThread() chrome/browser/data_use_measurement/page_load_capping/page_load_capping_browsertest.cc:80

  This frame has 18 object(s):
    [32, 488) 'https_test_server' (line 81)
    [560, 688) 'listener' (line 86) <== Memory access at offset 560 is inside this variable
    [720, 744) 'ref.tmp' (line 92)
    [784, 800) 'gtest_ar_' (line 94)
    [816, 824) 'ref.tmp4' (line 94)
    [848, 856) 'temp.lvalue'
    [880, 904) 'ref.tmp5' (line 94)
    [944, 1064) 'ref.tmp9' (line 97)
    [1104, 1128) 'ref.tmp10' (line 97)
    [1168, 1192) 'handles' (line 104)
    [1232, 1256) 'create_image_script' (line 112)
    [1296, 1320) 'ref.tmp14' (line 113)
    [1360, 1384) 'ref.tmp15' (line 113)
    [1424, 1440) 'gtest_ar_18' (line 118)
    [1456, 1464) 'ref.tmp20' (line 118)
    [1488, 1496) 'ref.tmp26' (line 118)
    [1520, 1528) 'temp.lvalue27'
    [1552, 1576) 'ref.tmp28' (line 118)
HINT: this may be a false positive if your program uses some custom stack unwind mechanism, swapcontext or vfork
      (longjmp and C++ exceptions *are* supported)
SUMMARY: AddressSanitizer: stack-use-after-scope net/test/embedded_test_server/embedded_test_server.cc:436:27 in net::test_server::EmbeddedTestServer::HandleReadResult(net::test_server::HttpConnection*, int)
Shadow bytes around the buggy address:
  0x0fea13c03af0: f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5 f5
  0x0fea13c03b00: f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fea13c03b10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fea13c03b20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0fea13c03b30: 00 00 00 00 00 00 00 00 00 00 00 00 00 f2 f2 f2
=>0x0fea13c03b40: f2 f2 f2 f2 f2 f2[f8]f8 f8 f8 f8 f8 f8 f8 f8 f8
  0x0fea13c03b50: f8 f8 f8 f8 f8 f8 f2 f2 f2 f2 f8 f8 f8 f2 f2 f2
  0x0fea13c03b60: f2 f2 f8 f8 f2 f2 f8 f2 f2 f2 00 f2 f2 f2 f8 f8
  0x0fea13c03b70: f8 f2 f2 f2 f2 f2 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
  0x0fea13c03b80: f8 f8 f8 f8 f8 f2 f2 f2 f2 f2 f8 f8 f8 f2 f2 f2
  0x0fea13c03b90: f2 f2 f8 f8 f8 f2 f2 f2 f2 f2 f8 f8 f8 f2 f2 f2
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
  Shadow gap:              cc
Thread T30 (EmbeddedTestSer) created by T0 (browser_tests) here:
    #0 0x8355b5d in __interceptor_pthread_create /b/build/slave/linux_upload_clang/build/src/third_party/llvm/compiler-rt/lib/asan/asan_interceptors.cc:210:3
    #1 0x154abdac in base::(anonymous namespace)::CreateThread(unsigned long, bool, base::PlatformThread::Delegate*, base::PlatformThreadHandle*, base::ThreadPriority) base/threading/platform_thread_posix.cc:115:13
    #2 0x153c28a6 in base::Thread::StartWithOptions(base::Thread::Options const&) base/threading/thread.cc:112:15
    #3 0x154e0131 in net::test_server::EmbeddedTestServer::StartAcceptingConnections() net/test/embedded_test_server/embedded_test_server.cc:177:3
    #4 0x154de5d9 in net::test_server::EmbeddedTestServer::Start() net/test/embedded_test_server/embedded_test_server.cc:94:3
    #5 0x88acd38 in PageLoadCappingBrowserTest_PageLoadCappingBlocksLoadsAndResume_Test::RunTestOnMainThread() chrome/browser/data_use_measurement/page_load_capping/page_load_capping_browsertest.cc:94:3
    #6 0x1696bdf1 in content::BrowserTestBase::ProxyRunTestOnMainThreadLoop() content/public/test/browser_test_base.cc:385:5
    #7 0x15689b28 in Run base/callback.h:125:12
    #8 0x15689b28 in ChromeBrowserMainParts::PreMainMessageLoopRunImpl() chrome/browser/chrome_browser_main.cc:2134
    #9 0x15686b9b in ChromeBrowserMainParts::PreMainMessageLoopRun() chrome/browser/chrome_browser_main.cc:1520:18
    #10 0xf97c394 in content::BrowserMainLoop::PreMainMessageLoopRun() content/browser/browser_main_loop.cc:966:13
    #11 0x10b5a0d7 in Run base/callback.h:125:12
    #12 0x10b5a0d7 in content::StartupTaskRunner::RunAllTasksNow() content/browser/startup_task_runner.cc:44
    #13 0xf977e44 in content::BrowserMainLoop::CreateStartupTasks() content/browser/browser_main_loop.cc:877:25
    #14 0xf9859ba in content::BrowserMainRunnerImpl::Initialize(content::MainFunctionParams const&, std::__1::unique_ptr<content::BrowserProcessSubThread, std::__1::default_delete<content::BrowserProcessSubThread> >) content/browser/browser_main_runner_impl.cc:148:15
    #15 0xf970b71 in content::BrowserMain(content::MainFunctionParams const&, std::__1::unique_ptr<content::BrowserProcessSubThread, std::__1::default_delete<content::BrowserProcessSubThread> >) content/browser/browser_main.cc:47:20
    #16 0x14d8f31c in content::RunBrowserProcessMain(content::MainFunctionParams const&, content::ContentMainDelegate*, std::__1::unique_ptr<content::BrowserProcessSubThread, std::__1::default_delete<content::BrowserProcessSubThread> >) content/app/content_main_runner_impl.cc:620:10
    #17 0x14d91ee0 in content::ContentMainRunnerImpl::Run() content/app/content_main_runner_impl.cc:964:12
    #18 0x1bfecf7b in service_manager::Main(service_manager::MainParams const&) services/service_manager/embedder/main.cc:459:29
    #19 0x14d8c100 in content::ContentMain(content::ContentMainParams const&) content/app/content_main.cc:19:10
    #20 0x1696aa17 in content::BrowserTestBase::SetUp() content/public/test/browser_test_base.cc:323:3
    #21 0x1555eb1d in InProcessBrowserTest::SetUp() chrome/test/base/in_process_browser_test.cc:244:20
    #22 0xc8444e2 in testing::Test::Run() third_party/googletest/src/googletest/src/gtest.cc
    #23 0xc8468a4 in testing::TestInfo::Run() third_party/googletest/src/googletest/src/gtest.cc:2667:11
    #24 0xc847cb6 in testing::TestCase::Run() third_party/googletest/src/googletest/src/gtest.cc:2785:28
    #25 0xc86d9e6 in testing::internal::UnitTestImpl::RunAllTests() third_party/googletest/src/googletest/src/gtest.cc:5047:43
    #26 0xc86cc12 in testing::UnitTest::Run() third_party/googletest/src/googletest/src/gtest.cc
    #27 0x155abd27 in RUN_ALL_TESTS third_party/googletest/src/googletest/include/gtest/gtest.h:2329:46
    #28 0x155abd27 in base::TestSuite::Run() base/test/test_suite.cc:275
    #29 0x151bfa0f in ChromeTestSuiteRunner::RunTestSuite(int, char**) chrome/test/base/chrome_test_launcher.cc:65:38
    #30 0x169ffae3 in content::LaunchTests(content::TestLauncherDelegate*, unsigned long, int, char**) content/public/test/test_launcher.cc:625:31
    #31 0x151c07ea in LaunchChromeTests(unsigned long, content::TestLauncherDelegate*, int, char**) chrome/test/base/chrome_test_launcher.cc:170:10
    #32 0x151bf80b in main chrome/test/base/browser_tests_main.cc:36:10
    #33 0x7f4ca5ba6f44 in __libc_start_main /build/eglibc-ripdx6/eglibc-2.19/csu/libc-start.c:287

Cannot upload crash dump: failed to open
==22708==ABORTING
[22828:22828:0603/045011.418902:WARNING:x11_util.cc(1378)] X error received: serial 170, error_code 3 (BadWindow (invalid Window parameter)), request_code 4, minor_code 0 (X_DestroyWindow)
[0603/045011.427499:ERROR:nacl_helper_linux.cc(310)] NaCl helper process running without a sandbox!
Most likely you need to configure your SUID sandbox correctly
[17/249] PageLoadCappingBrowserTest.PageLoadCappingBlocksLoadsAndResume (CRASHED)

I am going to disable PageLoadCappingBrowserTest.PageLoadCappingBlocksLoads but leave PageLoadCappingBrowserTest.PageLoadCappingBlocksLoadsAndResume as it looks too risky to to get lost.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e26b69291606c33e57571d61fb0d6695ce773ea4

commit e26b69291606c33e57571d61fb0d6695ce773ea4
Author: Dominic Battre <battre@chromium.org>
Date: Mon Jun 04 11:33:02 2018

Disable PageLoadCappingBrowserTest.PageLoadCappingBlocksLoads

TBR=ryansturm@chromium.org

Bug:  848675 , 797979 
Change-Id: Id894cc74258c4f9cd08c2566f3e81f400920dede
Reviewed-on: https://chromium-review.googlesource.com/1084832
Reviewed-by: Dominic Battré <battre@chromium.org>
Commit-Queue: Dominic Battré <battre@chromium.org>
Cr-Commit-Position: refs/heads/master@{#564058}
[modify] https://crrev.com/e26b69291606c33e57571d61fb0d6695ce773ea4/chrome/browser/data_use_measurement/page_load_capping/page_load_capping_browsertest.cc

Thanks, battre@ I'll look into finding a better way to write these tests.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d47abb700fd7714183c33d1fd35e5c1b56809042

commit d47abb700fd7714183c33d1fd35e5c1b56809042
Author: Ryan Sturm <ryansturm@chromium.org>
Date: Tue Jun 05 20:32:59 2018

Making the page capping browser test robust

This test suite now handles requests instead of looking at connections
and tracks the count of requests based on a specific URL pattern. The
first test will pass when no image requests have been loaded, so if for
some reason 20 round trips to the renderer do not gaurantee the request
is seen on the net/ stack, the test will still pass. The second test
creates an image request while the page is paused, and upon unpausing
the page, waits for the image request to be seen in the embedded test
server. The third test loads the image in the same pattern as the second
without ever pausing the page.

Bug:  848675 
Change-Id: I5a72cf1765b583bdb83ade2046366c12d6d70613
Reviewed-on: https://chromium-review.googlesource.com/1086125
Commit-Queue: Ryan Sturm <ryansturm@chromium.org>
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#564645}
[modify] https://crrev.com/d47abb700fd7714183c33d1fd35e5c1b56809042/chrome/browser/data_use_measurement/page_load_capping/page_load_capping_browsertest.cc

The latest patch should remove flakes unless there are real problems in the code.

Findit identified the culprit r564933 with confidence 82.9% in the config "chromium.memory / Linux MSan Tests"
based on the flakiness trend:

https://findit-for-me.appspot.com/waterfall/flake?key=ag9zfmZpbmRpdC1mb3ItbWVyswELEhdNYXN0ZXJGbGFrZUFuYWx5c2lzUm9vdCJ9Y2hyb21pdW0ubWVtb3J5L0xpbnV4IE1TYW4gVGVzdHMvMTAyNTcvYnJvd3Nlcl90ZXN0cy9VR0ZuWlV4dllXUkRZWEJ3YVc1blFuSnZkM05sY2xSbGMzUXVVR0ZuWlV4dllXUkRZWEJ3YVc1blFteHZZMnR6VEc5aFpITT0MCxITTWFzdGVyRmxha2VBbmFseXNpcxgBDA


Automatically posted by the findit-for-me app (https://goo.gl/Ot9f7N).
Feedback is welcome! Please use component Tools>Test>FindIt>Flakiness