vtkStdString cstor does not support NULL pointer
vtkStdString cstor does not support NULL pointer

Change-Id: I34503fb732b947ab943c1da5e8045b5da966baf6

cjh1/VTK,berendkleinhaneveld/VTK,johnkit/vtk-dev,keithroe/vtkoptix,daviddoria/PointGraphsPhase1,sumedhasingla/VTK,hendradarwin/VTK,cjh1/VTK,gram526/VTK,candy7393/VTK,daviddoria/PointGraphsPhase1,jmerkow/VTK,hendradarwin/VTK,SimVascular/VTK,hendradarwin/VTK,berendkleinhaneveld/VTK,mspark93/VTK,candy7393/VTK,ashray/VTK-EVM,sankhesh/VTK,aashish24/VTK-old,sankhesh/VTK,ashray/VTK-EVM,cjh1/VTK,demarle/VTK,cjh1/VTK,jmerkow/VTK,keithroe/vtkoptix,cjh1/VTK,keithroe/vtkoptix,jmerkow/VTK,demarle/VTK,biddisco/VTK,hendradarwin/VTK,keithroe/vtkoptix,gram526/VTK,hendradarwin/VTK,SimVascular/VTK,biddisco/VTK,sumedhasingla/VTK,mspark93/VTK,ashray/VTK-EVM,daviddoria/PointGraphsPhase1,gram526/VTK,sankhesh/VTK,johnkit/vtk-dev,SimVascular/VTK,daviddoria/PointGraphsPhase1,mspark93/VTK,mspark93/VTK,spthaolt/VTK,berendkleinhaneveld/VTK,aashish24/VTK-old,collects/VTK,biddisco/VTK,cjh1/VTK,sumedhasingla/VTK,biddisco/VTK,berendkleinhaneveld/VTK,sumedhasingla/VTK,sankhesh/VTK,sankhesh/VTK,aashish24/VTK-old,spthaolt/VTK,collects/VTK,johnkit/vtk-dev,collects/VTK,demarle/VTK,demarle/VTK,spthaolt/VTK,aashish24/VTK-old,demarle/VTK,SimVascular/VTK,daviddoria/PointGraphsPhase1,gram526/VTK,mspark93/VTK,candy7393/VTK,candy7393/VTK,berendkleinhaneveld/VTK,sankhesh/VTK,demarle/VTK,msmolens/VTK,spthaolt/VTK,SimVascular/VTK,sankhesh/VTK,jmerkow/VTK,msmolens/VTK,jmerkow/VTK,gram526/VTK,msmolens/VTK,candy7393/VTK,spthaolt/VTK,aashish24/VTK-old,spthaolt/VTK,sumedhasingla/VTK,hendradarwin/VTK,ashray/VTK-EVM,ashray/VTK-EVM,candy7393/VTK,demarle/VTK,msmolens/VTK,ashray/VTK-EVM,gram526/VTK,berendkleinhaneveld/VTK,mspark93/VTK,sankhesh/VTK,jmerkow/VTK,biddisco/VTK,SimVascular/VTK,hendradarwin/VTK,ashray/VTK-EVM,mspark93/VTK,collects/VTK,msmolens/VTK,aashish24/VTK-old,jmerkow/VTK,msmolens/VTK,johnkit/vtk-dev,collects/VTK,demarle/VTK,sumedhasingla/VTK,berendkleinhaneveld/VTK,gram526/VTK,candy7393/VTK,mspark93/VTK,msmolens/VTK,daviddoria/PointGraphsPhase1,SimVascular/VTK,johnkit/vtk-dev,sumedhasingla/VTK,sumedhasingla/VTK,candy7393/VTK,keithroe/vtkoptix,jmerkow/VTK,spthaolt/VTK,msmolens/VTK,SimVascular/VTK,keithroe/vtkoptix,johnkit/vtk-dev,gram526/VTK,biddisco/VTK,biddisco/VTK,keithroe/vtkoptix,collects/VTK,keithroe/vtkoptix,johnkit/vtk-dev,ashray/VTK-EVM