early initialization of its PopupMenu
(cherry picked from commit 5149ad822bb66cca9561b7c181c6c2279affc29a)
Conflicts:
framework/inc/uielement/popuptoolbarcontroller.hxx
framework/source/uielement/popuptoolbarcontroller.cxx
Change-Id: I619fe7b86a19b146079792a73a50d23682d04a3c