BUG: Fix unitialized variable that causes py_LabelStatistics test failure
Created by: msmolens
In a release build running the py_LabelStatistics test intermittently results in a hang or memory corruption.
This commit fixes the problem by initializing a member variable in vtkSlicerVolumesLogic. The member variable, and therefore the regression, was introduced in r23934 ("BUG: avoid false positives on geometry check"). The initial value matches what's described in the member variable's comment.
The unit test is updated to check the initial value of the member variable.