MAINT-3555 crash in LLPanel::~LLPanel() on shutdown:

indra/llcommon/llerror.cpp

indra/llcrashlogger/llcrashlogger.cpp

indra/llmessage/llhttpsender.cpp

indra/llmessage/llhttpsender.h

indra/llui/llpanel.h

indra/newview/llappviewerwin32.cpp

indra/newview/llcofwearables.cpp

indra/newview/llfloatercamera.cpp

indra/newview/llfloaterpreference.cpp

indra/newview/llfloatersocial.cpp

indra/newview/lloutfitslist.cpp

indra/newview/llpanelblockedlist.cpp

indra/newview/llpaneleditwearable.cpp

indra/newview/llpanelgroup.cpp

indra/newview/llpanelgroupgeneral.cpp

indra/newview/llpanelgrouplandmoney.cpp

indra/newview/llpanelgroupnotices.cpp

indra/newview/llpanelgrouproles.cpp

indra/newview/llpanelhome.cpp

indra/newview/llpanellandmarkinfo.cpp