fix missing attribute data in 2d xdmf structured grids
fix missing attribute data in 2d xdmf structured grids

Thanks Federico Bonelli for the patch.

Change-Id: Id135b454881c06b701aa1381cc8188e6c383a22d

mspark93/VTK,demarle/VTK,demarle/VTK,sumedhasingla/VTK,SimVascular/VTK,demarle/VTK,ashray/VTK-EVM,hendradarwin/VTK,candy7393/VTK,biddisco/VTK,msmolens/VTK,sankhesh/VTK,collects/VTK,sumedhasingla/VTK,ashray/VTK-EVM,sankhesh/VTK,gram526/VTK,mspark93/VTK,ashray/VTK-EVM,keithroe/vtkoptix,gram526/VTK,jmerkow/VTK,johnkit/vtk-dev,jmerkow/VTK,biddisco/VTK,collects/VTK,ashray/VTK-EVM,SimVascular/VTK,hendradarwin/VTK,johnkit/vtk-dev,mspark93/VTK,candy7393/VTK,candy7393/VTK,sankhesh/VTK,mspark93/VTK,berendkleinhaneveld/VTK,keithroe/vtkoptix,johnkit/vtk-dev,keithroe/vtkoptix,SimVascular/VTK,gram526/VTK,msmolens/VTK,gram526/VTK,sankhesh/VTK,ashray/VTK-EVM,gram526/VTK,sumedhasingla/VTK,mspark93/VTK,hendradarwin/VTK,ashray/VTK-EVM,msmolens/VTK,berendkleinhaneveld/VTK,gram526/VTK,johnkit/vtk-dev,SimVascular/VTK,collects/VTK,mspark93/VTK,candy7393/VTK,gram526/VTK,ashray/VTK-EVM,johnkit/vtk-dev,berendkleinhaneveld/VTK,jmerkow/VTK,sumedhasingla/VTK,berendkleinhaneveld/VTK,SimVascular/VTK,msmolens/VTK,sankhesh/VTK,sankhesh/VTK,sumedhasingla/VTK,demarle/VTK,collects/VTK,sumedhasingla/VTK,SimVascular/VTK,biddisco/VTK,gram526/VTK,hendradarwin/VTK,SimVascular/VTK,jmerkow/VTK,candy7393/VTK,biddisco/VTK,msmolens/VTK,keithroe/vtkoptix,msmolens/VTK,biddisco/VTK,candy7393/VTK,demarle/VTK,demarle/VTK,johnkit/vtk-dev,hendradarwin/VTK,berendkleinhaneveld/VTK,jmerkow/VTK,SimVascular/VTK,berendkleinhaneveld/VTK,sumedhasingla/VTK,biddisco/VTK,hendradarwin/VTK,msmolens/VTK,sankhesh/VTK,sankhesh/VTK,keithroe/vtkoptix,keithroe/vtkoptix,mspark93/VTK,jmerkow/VTK,hendradarwin/VTK,collects/VTK,candy7393/VTK,mspark93/VTK,keithroe/vtkoptix,ashray/VTK-EVM,sumedhasingla/VTK,johnkit/vtk-dev,jmerkow/VTK,msmolens/VTK,biddisco/VTK,keithroe/vtkoptix,collects/VTK,demarle/VTK,demarle/VTK,jmerkow/VTK,candy7393/VTK,berendkleinhaneveld/VTK