Re-enable fast scan on Windows tests (#1663)

Summary:
Fast-scan tests were disabled on windows because of a heap corruption. This diff enables them because the free_aligned bug was fixed in the meantime.

Pull Request resolved: https://github.com/facebookresearch/faiss/pull/1663

Reviewed By: beauby

Differential Revision: D26201040

Pulled By: mdouze

fbshipit-source-id: 8d6223b4e42ccb1ce2da6e2c51d9e0833199bde7

tests/test_fast_scan.py

@@ -328,7 +328,6 @@ class TestImplem15(TestImplems):
     def test_2_64(self):
         self.do_with_params(32, (2, 64))
 
-@unittest.skipIf(platform.system() == "Windows", "heap corruption on windows")
 class TestAdd(unittest.TestCase):
 
     def do_test_add(self, d, bbs):

tests/test_fast_scan_ivf.py

@@ -359,7 +359,6 @@ class TestIVFImplem13(TestIVFImplem12):
     IMPLEM = 13
 
 
-@unittest.skipIf(platform.system() == "Windows", "heap corruption on windows")
 class TestAdd(unittest.TestCase):
 
     def do_test(self, by_residual=False, metric=faiss.METRIC_L2, d=32, bbs=32):