Added checking for NULL pointer in a few locations
Added checking for NULL pointer in a few locations

Also added missing print out of member variable.

Change-Id: I9ea62ea7c60545fa2a6a5552c8dd8b98d2fdd093

candy7393/VTK,sumedhasingla/VTK,jmerkow/VTK,msmolens/VTK,candy7393/VTK,keithroe/vtkoptix,sumedhasingla/VTK,demarle/VTK,jmerkow/VTK,gram526/VTK,keithroe/vtkoptix,demarle/VTK,sankhesh/VTK,SimVascular/VTK,keithroe/vtkoptix,msmolens/VTK,candy7393/VTK,demarle/VTK,SimVascular/VTK,candy7393/VTK,candy7393/VTK,keithroe/vtkoptix,sumedhasingla/VTK,gram526/VTK,msmolens/VTK,jmerkow/VTK,gram526/VTK,mspark93/VTK,msmolens/VTK,msmolens/VTK,msmolens/VTK,candy7393/VTK,keithroe/vtkoptix,mspark93/VTK,jmerkow/VTK,jmerkow/VTK,sankhesh/VTK,demarle/VTK,keithroe/vtkoptix,gram526/VTK,sankhesh/VTK,candy7393/VTK,demarle/VTK,jmerkow/VTK,demarle/VTK,mspark93/VTK,mspark93/VTK,sumedhasingla/VTK,gram526/VTK,mspark93/VTK,sumedhasingla/VTK,SimVascular/VTK,msmolens/VTK,sankhesh/VTK,mspark93/VTK,sankhesh/VTK,SimVascular/VTK,gram526/VTK,sumedhasingla/VTK,sumedhasingla/VTK,keithroe/vtkoptix,gram526/VTK,keithroe/vtkoptix,candy7393/VTK,SimVascular/VTK,demarle/VTK,jmerkow/VTK,mspark93/VTK,sankhesh/VTK,mspark93/VTK,gram526/VTK,SimVascular/VTK,msmolens/VTK,sankhesh/VTK,SimVascular/VTK,jmerkow/VTK,demarle/VTK,sankhesh/VTK,sumedhasingla/VTK,SimVascular/VTK