Remove extra test that was accidentally backported from the trunk

Lib/test/test_float.py

@@ -113,14 +113,6 @@ class IEEEFormatTestCase(unittest.TestCase):
             self.assertEquals(pos_pos(), neg_pos())
             self.assertEquals(pos_neg(), neg_neg())
 
-    if float.__getformat__("double").startswith("IEEE"):
-        def test_underflow_sign(self):
-            import math
-            # check that -1e-1000 gives -0.0, not 0.0
-            self.assertEquals(math.atan2(-1e-1000, -1), math.atan2(-0.0, -1))
-            self.assertEquals(math.atan2(float('-1e-1000'), -1),
-                              math.atan2(-0.0, -1))
-
 def test_main():
     test_support.run_unittest(
         FormatFunctionsTestCase,