Chrome Version       : 63.0.3213.3
OS Version: OS X 10.12.6

5 tests crashed:
    CompositingWidgetTest.Transparency_DesktopWidgetInferOpacity (../../ui/views/widget/widget_unittest.cc:3934)
    CompositingWidgetTest.Transparency_DesktopWidgetOpaque (../../ui/views/widget/widget_unittest.cc:3938)
    CompositingWidgetTest.Transparency_DesktopWidgetTranslucent (../../ui/views/widget/widget_unittest.cc:3942)
    NativeWidgetMacTest.ReparentNativeViewTypes (../../ui/views/widget/native_widget_mac_unittest.mm:1747)
    NativeWidgetTest.GetTopLevelNativeWidget2 (../../ui/views/widget/native_widget_unittest.cc:84)

E.g. with

void NativeWidgetMac::InitNativeWidget(const Widget::InitParams& params) {
  delegate_->OnNativeWidgetCreated(true);
  DCHECK(GetWidget()->GetRootView());  // Fine.
  DCHECK(GetWidget()->GetFocusManager());  // Fails.
...
}

I'm suggesting in https://chromium-review.googlesource.com/c/chromium/src/+/670479 that we add a check, but it's possible we don't want to support this use case.