Always addScalingVector from MooseVariableBase::initialSetup
Always addScalingVector from MooseVariableBase::initialSetup

There's no performance penalty to do thing this because this calls
through to SystemBase::addVector which checks whether we already have
the vector and if so, just returns it. And now that `addScalingVector`
happens much later in the simulation (e.g. during `initialSetup` instead
of during variable construction) we need to make sure that we always add
the vector, because this triggers retrieval of the vector in assembly.
If we kept the `hasVector` check in `MooseVariableBaes::initialSetup` we
would actually never trigger the vector retrieval in Assembly because
`hasVector` is now `true` by the time we arrive at
`MooseVariableBase::initialSetup`. This is because we have restored the
libmesh systems and vectors by this point in the simulation

idaholab/moose,andrsd/moose,jessecarterMOOSE/moose,bwspenc/moose,SudiptaBiswas/moose,nuclear-wizard/moose,laagesen/moose,milljm/moose,bwspenc/moose,lindsayad/moose,laagesen/moose,idaholab/moose,SudiptaBiswas/moose,idaholab/moose,lindsayad/moose,nuclear-wizard/moose,lindsayad/moose,jessecarterMOOSE/moose,harterj/moose,sapitts/moose,andrsd/moose,dschwen/moose,andrsd/moose,milljm/moose,jessecarterMOOSE/moose,SudiptaBiswas/moose,harterj/moose,andrsd/moose,sapitts/moose,nuclear-wizard/moose,laagesen/moose,milljm/moose,SudiptaBiswas/moose,lindsayad/moose,SudiptaBiswas/moose,milljm/moose,harterj/moose,jessecarterMOOSE/moose,laagesen/moose,harterj/moose,nuclear-wizard/moose,dschwen/moose,lindsayad/moose,milljm/moose,sapitts/moose,jessecarterMOOSE/moose,laagesen/moose,idaholab/moose,andrsd/moose,bwspenc/moose,dschwen/moose,harterj/moose,dschwen/moose,bwspenc/moose,sapitts/moose,dschwen/moose,sapitts/moose,bwspenc/moose,idaholab/moose