This recently started failing:
https://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=interactive_ui_tests&tests=TabDragging%2FDetachToBrowserTabDragControllerTest.DetachToOwnWindow%2F0

The failure is:
../../chrome/browser/ui/views/tabs/tab_drag_controller_interactive_uitest.cc:935: Failure
Value of: new_browser->window()->IsActive()
  Actual: false
Expected: true
Stack trace:
0   interactive_ui_tests                0x000000010128053b testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop(int) + 91
1   interactive_ui_tests                0x000000010127ff09 testing::internal::AssertHelper::operator=(testing::Message const&) const + 89
2   interactive_ui_tests                0x00000001011fe239 DetachToBrowserTabDragControllerTest_DetachToOwnWindow_Test::RunTestOnMainThread() + 3849
3   interactive_ui_tests                0x000000010374a21b content::BrowserTestBase::ProxyRunTestOnMainThreadLoop() + 491
4   interactive_ui_tests                0x000000010321515c ChromeBrowserMainParts::PreMainMessageLoopRunImpl() + 4364
5   interactive_ui_tests                0x0000000103213f4e ChromeBrowserMainParts::PreMainMessageLoopRun() + 62
6   interactive_ui_tests                0x0000000101dd9e63 content::BrowserMainLoop::PreMainMessageLoopRun() + 67
7   interactive_ui_tests                0x00000001021c6f07 content::StartupTaskRunner::RunAllTasksNow() + 39

I think this may have been caused by:
Remove makeKeyAndOrderFront: from WebContentsViewMac::Focus().
292ad04dc764c3ae4643f71f75b13afa7da4c745

I think this wasn't caught by the cq because it only happens on MacOS 10.10.

On the flakiness dashboard, the first failure is at:
http://build.chromium.org/p/chromium.mac/builders/Mac10.10%20Tests/builds/33682

The run before that succeeded:
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac10.10%20Tests/33681

Erik pointed out that this test may have been failing earlier (https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac10.10%20Tests/33674). It looks like it was, but for a different reason.

This has been reverted in https://chromium-review.googlesource.com/c/chromium/src/+/1130141.

Confirmed revert is successful.