BUG: Fixed segfault on the Mac.
BUG: Fixed segfault on the Mac.

Inconsistency between platforms - there was not always a valid context
on the Mac. Calling render on the view before checking capabilities
fixes it.

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