vtkDataSetSurfaceFilter had some funky code designed to optimize
(minimize) allocation of small objects. This required apparently
writing beyond the limits of an array. It was not a bug but made
tools like the clang sanitizer think that it was. Fixed it while
still maintaining the allocation optimization, at the cost of a
bit more memory usage.

Change-Id: I3ef7051e85601a4440f02cb4dfe2e15227a06e87