In fact the ScDocument::CalcFormulaTree() call in
WorkbookFragment::recalcFormulaCells() never did anything because
no formula cell was added to the tree. Only visible dirty cells
were recalculated, but not their dependents.

Change-Id: I11217fa19adb766f509d0d6854502112de547c59
Reviewed-on: https://gerrit.libreoffice.org/57431Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins