The infinite loop starts from ArcNotificationContentView::UpdateControlButtonsVisibility().


Stack trace:
#0  0x00005c5d5b27fcd2 in ash::Shell::GetAllRootWindows() () at ../../ash/shell.cc:310
#1  0x00005c5d5b2848c7 in ash::ShellPort::IsSystemModalWindowOpen() ()
    at ../../ash/shell_port.cc:86
#2  0x00005c5d5b2e2e5a in ash::SystemModalContainerEventFilter::OnEvent(ui::Event*) ()
    at ../../ash/wm/system_modal_container_event_filter.cc:21
#3  0x00005c5d59d3ca29 in ui::EventDispatcher::DispatchEventToEventHandlers(std::vector<ui::EventHandler*, std::allocator<ui::EventHandler*> >*, ui::Event*) ()
    at ../../ui/events/event_dispatcher.cc:191
#4  0x00005c5d59d3c6c5 in ui::EventDispatcher::ProcessEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:127
#5  0x00005c5d59d3c57c in ui::EventDispatcherDelegate::DispatchEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:86
#6  0x00005c5d5a55dae2 in aura::WindowEventDispatcher::DispatchMouseEnterOrExit(aura::Window*, ui::MouseEvent const&, ui::EventType) ()
    at ../../ui/aura/window_event_dispatcher.cc:303
#7  0x00005c5d5a55e3bc in aura::WindowEventDispatcher::DispatchMouseExitToHidingWindow(aura::Window*) () at ../../ui/aura/window_event_dispatcher.cc:178
#8  0x00005c5d5a5590e7 in aura::Window::SetVisible(bool) ()
    at ../../ui/aura/window.cc:716
#9  0x00005c5d59d3ca29 in ui::EventDispatcher::DispatchEventToEventHandlers(std::vector<ui::EventHandler*, std::allocator<ui::EventHandler*> >*, ui::Event*) ()
    at ../../ui/events/event_dispatcher.cc:191
#10 0x00005c5d59d3c6c5 in ui::EventDispatcher::ProcessEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:127
#11 0x00005c5d59d3c57c in ui::EventDispatcherDelegate::DispatchEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:86
#12 0x00005c5d5a55dae2 in aura::WindowEventDispatcher::DispatchMouseEnterOrExit(aura::Window*, ui::MouseEvent const&, ui::EventType) ()
    at ../../ui/aura/window_event_dispatcher.cc:303
#13 0x00005c5d5a55e3bc in aura::WindowEventDispatcher::DispatchMouseExitToHidingWindow(aura::Window*) () at ../../ui/aura/window_event_dispatcher.cc:178
#14 0x00005c5d5a5590e7 in aura::Window::SetVisible(bool) ()
    at ../../ui/aura/window.cc:716
#15 0x00005c5d59d3ca29 in ui::EventDispatcher::DispatchEventToEventHandlers(std::vector<ui::EventHandler*, std::allocator<ui::EventHandler*> >*, ui::Event*) ()
    at ../../ui/events/event_dispatcher.cc:191
#16 0x00005c5d59d3c6c5 in ui::EventDispatcher::ProcessEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:127
#17 0x00005c5d59d3c57c in ui::EventDispatcherDelegate::DispatchEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:86
#18 0x00005c5d5a55dae2 in aura::WindowEventDispatcher::DispatchMouseEnterOrExit(aura::Window*, ui::MouseEvent const&, ui::EventType) ()
    at ../../ui/aura/window_event_dispatcher.cc:303
#19 0x00005c5d5a55e3bc in aura::WindowEventDispatcher::DispatchMouseExitToHidingWindow(aura::Window*) () at ../../ui/aura/window_event_dispatcher.cc:178
#20 0x00005c5d5a5590e7 in aura::Window::SetVisible(bool) ()
    at ../../ui/aura/window.cc:716
#21 0x00005c5d59d3ca29 in ui::EventDispatcher::DispatchEventToEventHandlers(std::vector<ui::EventHandler*, std::allocator<ui::EventHandler*> >*, ui::Event*) ()
    at ../../ui/events/event_dispatcher.cc:191
#22 0x00005c5d59d3c6c5 in ui::EventDispatcher::ProcessEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:127
#23 0x00005c5d59d3c57c in ui::EventDispatcherDelegate::DispatchEvent(ui::EventTarget*, ui::Event*) () at ../../ui/events/event_dispatcher.cc:86
#24 0x00005c5d5a55dae2 in aura::WindowEventDispatcher::DispatchMouseEnterOrExit(aura::Window*, ui::MouseEvent const&, ui::EventType) ()
    at ../../ui/aura/window_event_dispatcher.cc:303
...

CL: https://chromium-review.googlesource.com/c/chromium/src/+/697406

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/88a32c820aea50c2f4adf0bb86a64b64a9f36e07

commit 88a32c820aea50c2f4adf0bb86a64b64a9f36e07
Author: yoshiki iguchi <yoshiki@chromium.org>
Date: Thu Oct 05 13:48:31 2017

Add a guard to prevent an infinite loop in arc notification

In some case, an infinite loop happens in ArcNotificationContent::
UpdateControlButtonVisiblity() method.
The logic is: UpdateControlButtonsVisiblity() tries hiding the control
buttons, it generates a mouse exit event, and the event handler calls
UpdateControlButtonsVisibility.

To prevent that, this patch adds the flag to prevent the calling the
method during the method.

Bug:  771084 
Test: manual
Change-Id: I03f9d5c00eb3c7f39bebebec03bfeb51616ca925
Reviewed-on: https://chromium-review.googlesource.com/697406
Reviewed-by: Yuichiro Hanada <yhanada@chromium.org>
Reviewed-by: Eliot Courtney <edcourtney@chromium.org>
Commit-Queue: Yoshiki Iguchi <yoshiki@chromium.org>
Cr-Commit-Position: refs/heads/master@{#506715}
[modify] https://crrev.com/88a32c820aea50c2f4adf0bb86a64b64a9f36e07/ui/arc/notification/arc_notification_content_view.cc
[modify] https://crrev.com/88a32c820aea50c2f4adf0bb86a64b64a9f36e07/ui/arc/notification/arc_notification_content_view.h

Not seeing this crash anymore, on M64 dev build (10124.0.0, 64.0.3265.0).