Today, RichEditWndProc_common assumes that ITextServices::TxDraw
preserves the brush selection of the given device context.  However,
this invariant may be broken by misbehaving embedded OLE objects in the
text document.

Fix this by not assuming that the return value of the second
SelectObject() call equals the brush passed to the first SelectObject()
call in RichEditWndProc_common's WM_PAINT / WM_PRINTCLIENT case.