Fix bug (no swap buffer) when running on one proc.
Fix bug (no swap buffer) when running on one proc.

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