[QMTrack] modification to issue scalar_advection_2d

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The issue scalar_advection_2d was changed by oldham on 2001-10-09 20:18 MDT.

The following fields were modified:

  Discussion: 
      On 2001-10-09 20:18 MDT, oldham wrote: JDO writes: The problem 
      occurs possilby because periodic boundary conditions are applied 
      to all mesh faces of a field "u" that is cell centered.  Is this 
      reasonable?  Should the code use a PInsist checking the centering 
      type?