Fix numerical precision problem in vtkCellLocator::IntersectWithLine

Change-Id: I07e71146fbd6f8e68661cdc941b9a0c473613144
Add default value for argument

Change-Id: I89511c45e4c4c0f585d9c04eaca0131066db975b
Merge topic 'vtkCellLocator-precision-issue' into master

949ffbf8 Add default value for argument
e7438f2d Fix numerical precision problem in vtkCellLocator::IntersectWithLine