This commit replaces the solution in revision 44539.
It is recalled that a degenerate triangle is a triangle such that
1) A and B are in the same position in the 3D space; or
2) the distance between point P and line segment AB is zero.
Degenerate triangles in the second form are now resolved by adding a
small offset to P (i.e., the resulting triangles have a non-zero area).
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