ToolBarManager::Implementation::Update in sd/source/ui/view/ToolBarManager.cxx
is dubious.  It takes its parameter by value (so in UnlockUpdate() the passed-in
mpSynchronousLayouterLock is reset upon passing it in), but the comment that it
"is [...] released at its end" together with the redundant
pLocalLayouterLock.reset() at the end of Update() make it look as though the
intention was to pass by reference.  However, resetting
mpSynchronousLayouterLock even in the case where pass-by-ref would fail to reset
it is apparently important, as otherwise e.g. JunitTest_svx_unoapi would run
into the OSL_ASSERT(mpSynchronousLayouterLock.get()==NULL) in LockUpdate() with
a call stack of ... -> Update -> SetValid -> UpdateLockImplementation ->
LockUpdate.

Change-Id: I7d2717d5e1f8aa69c79a626c100d7fefb0cfb120