50cf7cae introduced a regression that
makes the smoketest fail on Windows (though strangely not on Linux),
because it removed the special handling of null pointers in the
SfxBroadcaster's listener array.  It is evidently possible that
a listener may be either added or removed at the SfxBroadcaster
while that SfxBroadcaster is currently doing a Broadcast, hence
AddListener and RemoveListener must be careful not to make the in
progress iteration through the listener array fail.

svllo.dll!SfxBroadcaster::AddListener(SfxListener & rListener={...}) Line 114 + 0x43 bytes   C++
svllo.dll!SfxListener::StartListening(SfxBroadcaster & rBroadcaster={...}, unsigned char bPreventDups=0)  Line 89  C++
sfxlo.dll!SfxPrintHelper::initialize(const com::sun::star::uno::Sequence<com::sun::star::uno::Any> & aArguments={...})  Line 162 C++
sfxlo.dll!SfxBaseModel::impl_getPrintHelper()  Line 3693    C++
sfxlo.dll!SfxBaseModel::Notify(SfxBroadcaster & rBC={...}, const SfxHint & rHint={...})  Line 2583   C++
svllo.dll!SfxBroadcaster::Broadcast(const SfxHint & rHint={...}) Line 56 + 0xb bytes C++
sfxlo.dll!SfxApplication::NotifyEvent(const SfxEventHint & rEventHint={...}, bool bSynchron=true)  Line 918    C++
sfxlo.dll!SfxObjectShell::SetInitialized_Impl(const bool i_fromInitNew=true)  Line 1146 + 0x37 bytes C++
sfxlo.dll!SfxObjectShell::FinishedLoading(unsigned short nFlags=3) Line 1302   C++

Change-Id: Id27d08faaa2472b57947960a92f19c44df55b72b