Avoid circular calls to `vtkRenderWindow::Render`.
vtkRenderWindow::Render
calls vtkRenderWindowInteractor::Initialize
,
which calls the vtkRenderWindow::Render
again! That's a bug. It
doesn't make sense for interactor to call Render()
. We don't encounter
this code (except in rare cases e.g. using EGL) since the
vtkRenderWindowInteractor subclasses don't call the superclass
implementation for Initialize
.