Actually execute the tests for the getter/setter/deleter tests on properties.

Also fix the test by having the test classes inherit from object.

Are the getter/setter/deleter attributes supposed to be able to chain?  As of
right now they can't as the property tries to call what the property returns,
which is another property when they are chained.

Lib/test/test_descr.py

@@ -2131,7 +2131,7 @@ def properties():
 
 
 def properties_plus():
-    class C:
+    class C(object):
         foo = property(doc="hello")
         @foo.getter
         def foo(self):
@@ -2146,8 +2146,11 @@ def properties_plus():
     assert C.foo.__doc__ == "hello"
     assert not hasattr(c, "foo")
     c.foo = -42
+    assert hasattr(c, '_foo')
+    assert c._foo == 42
     assert c.foo == 42
     del c.foo
+    assert not hasattr(c, '_foo')
     assert not hasattr(c, "foo")
 
     class D(C):
@@ -2163,20 +2166,20 @@ def properties_plus():
     del d.foo
     del d.foo
 
-    class E:
+    class E(object):
         @property
         def foo(self):
             return self._foo
         @foo.setter
-        def foo (self, value):
+        def foo(self, value):
             raise RuntimeError
         @foo.setter
+        def foo(self, value):
+            self._foo = abs(value)
         @foo.deleter
         def foo(self, value=None):
-            if value is None:
-                del self._foo
-            else:
-                self._foo = abs(value)
+            del self._foo
+
     e = E()
     e.foo = -42
     assert e.foo == 42
@@ -2193,6 +2196,7 @@ def properties_plus():
     f.foo = -10
     assert f.foo == 0
     del f.foo
+    print "*** HIT"
 
 
 def supers():
@@ -4477,6 +4481,7 @@ def test_main():
     recursions()
     weakrefs()
     properties()
+    properties_plus()
     supers()
     inherits()
     keywords()