Revert "Catch expected warning in sklearn/tests/test_naive_bayes.py (part of #2274)"

Apparently the behavior of the filter is not consistent across platforms and causes test
to fail on some of them...

This reverts commit b9cc3a72342dcac515bce8f49e02c23db3daf1be.
PY3K remove __pycache__ in make clean
neighbors numpy1.3 compat: fix typedefs, regen with cython 0.19
numpy 1.3 compat: use explicit type definitions
numpy 1.3 compat: make neighbors/dist_metrics compatible
COMPAT: empty_like does not have a dtype in np 1.3
COMPAT: make NeighborsHeap compatible with numpy 1.3
COMPAT: make NodeHeap compatible with numpy 1.3
COMPAT: make BinaryTree class compatible with numpy 1.3
COMPAT: make BallTree & KDTree compatible with numpy 1.3
COMPAT: last few BallTree/KDTree numpy 1.3 issues
COMPAT: fix arpack and pls on old scipy/numpy
COMPAT: string formatting syntax in Py 2.6
COMPAT: median and nans in old numpys
COMPAT: no assert_warns in np 1.3
FIX PY3K warning.catch_filter set record