Fixed null deref by returning upon error
Fixed null deref by returning upon error

Change-Id: Ide321068640c611d019edc3ee4c0fe6149da7ed3

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