Crash stack:

Program received signal SIGSEGV, Segmentation fault.
ash::SpecialPopupRow::AddViewAfterContent (this=0x0, view=0xad26dcf9820, 
    add_separator=false)
    at ../../ash/common/system/tray/special_popup_row.cc:139
139	  if (!views_after_content_container_) {
(gdb) bt
#0  ash::SpecialPopupRow::AddViewAfterContent (this=0x0, view=0xad26dcf9820, 
    add_separator=false)
    at ../../ash/common/system/tray/special_popup_row.cc:139
#1  0x00007fffe89e36ff in ash::SpecialPopupRow::AddViewAfterContent (this=0x0, 
    view=0xad26dcf9820)
    at ../../ash/common/system/tray/special_popup_row.cc:134
#2  0x00007fffe89e36cd in ash::SpecialPopupRow::AddViewToTitleRow (this=0x0, 
    view=0xad26dcf9820) at ../../ash/common/system/tray/special_popup_row.cc:91
#3  0x00007fffe898790a in ash::tray::NetworkStateListDetailedView::CreateExtraTitleRowButtons (this=0xad26fad7520)
    at ../../ash/common/system/chromeos/network/network_state_list_detailed_view.cc:510
#4  0x00007fffe8a4ed3c in ash::TrayDetailsView::CreateTitleRow (
    this=0xad26fad7520, string_id=23640)
    at ../../ash/common/system/tray/tray_details_view.cc:351
#5  0x00007fffe898647b in ash::tray::NetworkStateListDetailedView::Init (
    this=0xad26fad7520)
    at ../../ash/common/system/chromeos/network/network_state_list_detailed_view.cc:377
#6  0x00007fffe898bf9d in ash::TrayNetwork::CreateDetailedView (
    this=0xad26e122ec0, status=ash::LoginStatus::NOT_LOGGED_IN)
    at ../../ash/common/system/chromeos/network/tray_network.cc:287
#7  0x00007fffe89eea7f in ash::SystemTrayBubble::CreateItemViews (
---Type <return> to continue, or q <return> to quit---
    this=0xad26f0f2c80, login_status=ash::LoginStatus::NOT_LOGGED_IN)
    at ../../ash/common/system/tray/system_tray_bubble.cc:327
#8  0x00007fffe89ee5bf in ash::SystemTrayBubble::UpdateView (
    this=0xad26f0f2c80, 
    items=std::__debug::vector of length 1, capacity 1 = {...}, 
    bubble_type=ash::SystemTrayBubble::BUBBLE_TYPE_DETAILED)
    at ../../ash/common/system/tray/system_tray_bubble.cc:145
#9  0x00007fffe89e5888 in ash::SystemTray::ShowItems (this=0xad26e185e20, 
    items=std::__debug::vector of length 1, capacity 1 = {...}, detailed=true, 
    can_activate=true, creation_type=ash::BUBBLE_USE_EXISTING, 
    persistent=false) at ../../ash/common/system/tray/system_tray.cc:555
#10 0x00007fffe89e5d4e in ash::SystemTray::ShowDetailedView (
    this=0xad26e185e20, item=0xad26e122ec0, close_delay=0, activate=true, 
    creation_type=ash::BUBBLE_USE_EXISTING)
    at ../../ash/common/system/tray/system_tray.cc:374
#11 0x00007fffe89fa0c3 in ash::SystemTrayItem::TransitionDetailedView (
    this=0xad26e122ec0) at ../../ash/common/system/tray/system_tray_item.cc:43
#12 0x00007fffe8a59ec2 in ash::TrayItemMore::PerformAction (
    this=0xad26f6c9020, event=...)
    at ../../ash/common/system/tray/tray_item_more.cc:98
#13 0x00007fffe89de27b in ash::ActionableView::ButtonPressed (
    this=0xad26f6c9020, sender=0xad26f6c9028, event=...)
    at ../../ash/common/system/tray/actionable_view.cc:127
---Type <return> to continue, or q <return> to quit---
#14 0x00007fffea496137 in views::Button::NotifyClick (this=0xad26f6c9028, 
    event=...) at ../../ui/views/controls/button/button.cc:83
#15 0x00007fffea498ed7 in views::CustomButton::NotifyClick (
    this=0xad26f6c9028, event=...)
    at ../../ui/views/controls/button/custom_button.cc:465
#16 0x00007fffea4981c6 in views::CustomButton::OnMouseReleased (
    this=0xad26f6c9028, event=...)
    at ../../ui/views/controls/button/custom_button.cc:198
#17 0x00007fffea5723e2 in views::View::ProcessMouseReleased (
    this=0xad26f6c9028, event=...) at ../../ui/views/view.cc:2248
#18 0x00007fffea571d47 in views::View::OnMouseEvent (this=0xad26f6c9028, 
    event=0x7fffffff87a8) at ../../ui/views/view.cc:1021
#19 0x00007fffea4735f6 in views::InkDropHostView::OnMouseEvent (
    this=0xad26f6c9028, event=0x7fffffff87a8)
    at ../../ui/views/animation/ink_drop_host_view.cc:257
#20 0x00007fffea171c63 in ui::EventHandler::OnEvent (this=0xad26f6c90d8, 
    event=0x7fffffff87a8) at ../../ui/events/event_handler.cc:27
#21 0x00007fffea17a0a5 in ui::ScopedTargetHandler::OnEvent (
    this=0xad26f962290, event=0x7fffffff87a8)
    at ../../ui/events/scoped_target_handler.cc:32
#22 0x00007fffea16d940 in ui::EventDispatcher::DispatchEvent (
    this=0x7fffffff84e8, handler=0xad26f962290, event=0x7fffffff87a8)
    at ../../ui/events/event_dispatcher.cc:191

<triage>Alexander, could you have a look?</triage>

This should be fixed in issue 666635.
Please reopen if this is still reproducible.