Add a test that I thought wouldn't work but apparently does

test/tests/subclass_getattribute.py

+# Setting __getattribute__ on a base class should invalidate ICs for subclasses
+
+class B(object):
+    pass
+
+class C(B):
+    pass
+
+def getattribute(self, attr):
+    return 1
+
+c = C()
+b = B()
+c.a = 0
+b.a = 0
+for i in xrange(150):
+    print i, b.a, c.a
+
+    if i == 120:
+        B.__getattribute__ = getattribute