Log of failed build :
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac10.13%20Tests/3767

[ RUN      ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: { "called f", "called f" }, which has 2 elements
Stack trace:
0   webkit_unit_tests                   0x000000010241ad2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x000000010241a6e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x00000001038106b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: {}
Stack trace:
0   webkit_unit_tests                   0x000000010241ad2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x000000010241a6e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x00000001038106b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
[  FAILED  ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled (3206 ms)
[ RUN      ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: { "called f", "called f" }, which has 2 elements
Stack trace:
0   webkit_unit_tests                   0x000000010130bd2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x000000010130b6e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x00000001027016b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: {}
Stack trace:
0   webkit_unit_tests                   0x000000010130bd2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x000000010130b6e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x00000001027016b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
[  FAILED  ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled (3304 ms)
[ RUN      ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: { "called f", "called f" }, which has 2 elements
Stack trace:
0   webkit_unit_tests                   0x0000000104d43d2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x0000000104d436e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x00000001061396b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: {}
Stack trace:
0   webkit_unit_tests                   0x0000000104d43d2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x0000000104d436e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x00000001061396b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
[  FAILED  ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled (3514 ms)
[ RUN      ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: { "called f", "called f" }, which has 2 elements
Stack trace:
0   webkit_unit_tests                   0x00000001068b8d2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x00000001068b86e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x0000000107cae6b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
../../third_party/blink/renderer/core/scheduler/throttling_test.cc:86: Failure
Value of: ConsoleMessages()
Expected: has 1 element that is equal to "called f"
  Actual: {}
Stack trace:
0   webkit_unit_tests                   0x00000001068b8d2b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   webkit_unit_tests                   0x00000001068b86e9 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   webkit_unit_tests                   0x0000000107cae6b9 blink::BackgroundRendererThrottlingTest_BackgroundRenderersAreThrottled_Test::TestBody() + 441
[  FAILED  ] BackgroundRendererThrottlingTest.BackgroundRenderersAreThrottled (3317 ms)

Hi farahcharab@, Seems it is related to your CL https://chromium-review.googlesource.com/c/chromium/src/+/1112248. Please take a look.Thanks.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2156a3880a02ce6b62baac1b181111887ff40073

commit 2156a3880a02ce6b62baac1b181111887ff40073
Author: Peng Huang <penghuang@chromium.org>
Date: Mon Jun 25 17:52:03 2018

Revert "Scheduler: Bug in FrameAndTaskPriorityExperiment."

This reverts commit 8fe6701fc9df2b7e625f474e9cc5eced57e6a2c6.

Reason for revert: webkit_unit_tests failing on chromium.mac/Mac10.13 Tests


Original change's description:
> Scheduler: Bug in FrameAndTaskPriorityExperiment.
> 
> LowPriorityForSubFrameThrottleableTask study isn't using is_subframe
> signal. That is, all throttleable tasks are assigned low priority
> regardles of the type of the frame.
> 
> Change-Id: I1e924ef483b458a9b0d21e81a91d275901b9cb37
> Reviewed-on: https://chromium-review.googlesource.com/1112248
> Commit-Queue: Farah Charab <farahcharab@chromium.org>
> Reviewed-by: Alexander Timin <altimin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#570043}

TBR=altimin@chromium.org,farahcharab@chromium.org

No-Presubmit: true
No-Tree-Checks: true
No-Try: true

Bug:  856255 
Change-Id: I0236f77b0f551610fca97a93c148c9016d8f7bb9
Reviewed-on: https://chromium-review.googlesource.com/1113838
Reviewed-by: Peng Huang <penghuang@chromium.org>
Commit-Queue: Peng Huang <penghuang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#570089}
[modify] https://crrev.com/2156a3880a02ce6b62baac1b181111887ff40073/third_party/blink/renderer/platform/scheduler/main_thread/frame_scheduler_impl.cc
[modify] https://crrev.com/2156a3880a02ce6b62baac1b181111887ff40073/third_party/blink/renderer/platform/scheduler/main_thread/frame_scheduler_impl_unittest.cc