Setting the MDI client's caption

It turns out that overriding WndProc() is *not* enough.

You have to *not* set the parent form's Text property in the
designer!
Moreover, you can't set it programmatically either. You have
to consistently
set the caption indirectly, via WndProc(). Perhaps the
caption is blitted,
and WM_SETTEXT is then ignored by some external code; I
really have no idea.

It turns out that if I avoid setting Text, the app's icon
but *not* its name
appears in the toolbar. So I still have some fiddling to
do.