Related: #i124392# fill in SidebarDockingWindow::DoDispose

(cherry picked from commit 952f581cb77f52e9aaa974496dc8d86b335cb424)

Conflicts:
	sfx2/inc/sfx2/sidebar/SidebarChildWindow.hxx
	sfx2/source/dialog/templdlg.cxx
	sfx2/source/inc/templdgi.hxx

Change-Id: Idf06437dfc45e02d9e2303df84d52ba0837de108