Products.ERP5Type.tests.ProcessingNodeTestCase: Make tic independent from the...

Products.ERP5Type.tests.ProcessingNodeTestCase: Make tic independent from the number of activities processed per tic.

That number was vastly decreased, causing tests to bail with "tic is
looping forever" for no good reason.
Convert such logic into a deadline one.

product/ERP5Type/tests/ProcessingNodeTestCase.py

 # -*- coding: utf-8 -*-
 import errno, logging, os, socket, time
+import itertools
 from threading import Thread
 from UserDict import IterableUserDict
 import Lifetime
@@ -279,11 +280,13 @@ class ProcessingNodeTestCase(ZopeTestCase.TestCase):
         ZopeTestCase._print('Executing pending activities ...')
         old_message_count = 0
       start = time.time()
-      count = 1000
+      deadline = start + 100 # This prevents an infinite loop.
       getMessageList = portal_activities.getMessageList
       message_list = getMessageList()
       message_count = len(message_list)
-      while message_count and not stop_condition(message_list):
+      for call_count in itertools.count():
+        if not message_count or stop_condition(message_list):
+          break
         if verbose and old_message_count != message_count:
           ZopeTestCase._print(' %i' % message_count)
           old_message_count = message_count
@@ -293,9 +296,7 @@ class ProcessingNodeTestCase(ZopeTestCase.TestCase):
           raise KeyboardInterrupt
         message_list = getMessageList()
         message_count = len(message_list)
-        # This prevents an infinite loop.
-        count -= 1
-        if not count or message_count and all(x.processing_node == -2
+        if time.time() >= deadline or message_count and all(x.processing_node == -2
                                               for x in message_list):
           # We're about to raise RuntimeError, but maybe we've reached
           # the stop condition, so check just once more:
@@ -308,7 +309,7 @@ class ProcessingNodeTestCase(ZopeTestCase.TestCase):
             error_message += str(e)
           raise RuntimeError(error_message)
         # This give some time between messages
-        if count % 10 == 0:
+        if call_count % 10 == 0:
           portal_activities.timeShift(3 * VALIDATION_ERROR_DELAY)
       if verbose:
         ZopeTestCase._print(' done (%.3fs)\n' % (time.time() - start))