COMP: Fixed compile warning - use the GLboolean return type.
COMP: Fixed compile warning - use the GLboolean return type.

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