Ensure we set the active shaders
Ensure we set the active shaders

Important for reuse of the shader program, we must detach from
the already attached shader first.

Change-Id: Ic220241134f053c716a231e3f6a281fa02d93f79

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