patches: make Shared.DC.Scripts.Bindings and ZPublisher.BeforeTraverse.MultiHook new-style classes

This backports parts of zope commit bb7837c66 (Explicitly make all
classes new-style., 2017-09-15) and 173658008 (Fix unpickling of instances
those base class changed to a new-style class. (#208), 2017-10-24).

This is done for two reasons:
 - so that business template XML are same when exported from zope4
   and from zope2
 - so that a business template created from zope4 can still be
   installed on zope2.

product/ERP5Type/ZopePatch.py

@@ -107,6 +107,8 @@ from Products.ERP5Type.patches import WSGITask
 if six.PY2:
   # XXX-zope4py3: urllib2 removed (see future/backports/urllib/request.py)
   from Products.ERP5Type.patches import urllib_opener
+from Products.ERP5Type.patches import SharedDCScriptsBindings
+from Products.ERP5Type.patches import ZPublisherBeforeTraverse
 
 # These symbols are required for backward compatibility
 from Products.ERP5Type.patches.PropertyManager import ERP5PropertyManager

product/ERP5Type/patches/SharedDCScriptsBindings.py

+import Shared.DC.Scripts.Bindings
+
+# Make Shared.DC.Scripts.Bindings a new style classes already on Zope2, so that
+# we can install business templates exported on Zope4 in Zope2 instances.
+_NameAssignments = Shared.DC.Scripts.Bindings.NameAssignments
+if not isinstance(_NameAssignments, type):
+  class NameAssignments(_NameAssignments, object):
+    def __init__(self, mapping=None):
+      if mapping is None:
+        mapping = {}
+      _NameAssignments.__init__(self, mapping)
+  NameAssignments.__module__ = _NameAssignments.__module__
+
+  Shared.DC.Scripts.Bindings.NameAssignments = NameAssignments

product/ERP5Type/patches/ZPublisherBeforeTraverse.py

+import ZPublisher.BeforeTraverse
+
+# Make ZPublisher.BeforeTraverse.MultiHook a new style classes already on
+# Zope2, so that we can install business templates exported on Zope4 in
+# Zope2 instances.
+_MultiHook = ZPublisher.BeforeTraverse.MultiHook
+if not isinstance(_MultiHook, type):
+  class MultiHook(_MultiHook, object):
+    def __init__(self, hookname='<undefined hookname>', prior=None,
+                 defined_in_class=False):
+      _MultiHook.__init__(self, hookname, prior, defined_in_class)
+    def __repr__(self):
+      # BBB keep the old class repr for testBeforeTraverse
+      return '<ZPublisher.BeforeTraverse.MultiHook instance at 0x%0x (patched in %r)>' % (
+        id(self), __file__)
+  MultiHook.__module__ = _MultiHook.__module__
+
+  ZPublisher.BeforeTraverse.MultiHook = MultiHook