group_by in ansible 2.9.11 reports as changed breaking idempotence

fix-ansible-group_by.patch

Commit:  f9c3c6cba6f74f9c50c023389bf8f37a8534ada1
Date:    Wed Jul 29 10:44:46 2020 -0400
Message: Allow changed/failed mgmt on strategy actions (#70919)
--- a/ansible/plugins/strategy/__init__.py
+++ b/ansible/plugins/strategy/__init__.py
@@ -37,11 +37,11 @@ from ansible.errors import AnsibleError, AnsibleFileNotFound, AnsibleParserError
 from ansible.executor import action_write_locks
 from ansible.executor.process.worker import WorkerProcess
 from ansible.executor.task_result import TaskResult
-from ansible.inventory.host import Host
 from ansible.module_utils.six.moves import queue as Queue
 from ansible.module_utils.six import iteritems, itervalues, string_types
 from ansible.module_utils._text import to_text
 from ansible.module_utils.connection import Connection, ConnectionError
+from ansible.playbook.conditional import Conditional
 from ansible.playbook.handler import Handler
 from ansible.playbook.helpers import load_list_of_blocks
 from ansible.playbook.included_file import IncludedFile
@@ -78,6 +78,22 @@ class StrategySentinel:
 _sentinel = StrategySentinel()


+def post_process_whens(result, task, templar):
+
+    cond = None
+    if task.changed_when:
+        cond = Conditional(loader=templar._loader)
+        cond.when = task.changed_when
+        result['changed'] = cond.evaluate_conditional(templar, templar.available_variables)
+
+    if task.failed_when:
+        if cond is None:
+            cond = Conditional(loader=templar._loader)
+        cond.when = task.failed_when
+        failed_when_result = cond.evaluate_conditional(templar, templar.available_variables)
+        result['failed_when_result'] = result['failed'] = failed_when_result
+
+
 def results_thread_main(strategy):
     while True:
         try:
@@ -643,10 +659,12 @@ class StrategyBase:
                         new_host_info = result_item.get('add_host', dict())
                         self._add_host(new_host_info, iterator)
+                        post_process_whens(result_item, original_task, handler_templar)

                     elif 'add_group' in result_item:
                         # this task added a new group (group_by module)
                         self._add_group(original_host, result_item)
+                        post_process_whens(result_item, original_task, handler_templar)

                     if 'ansible_facts' in result_item:
                         # if delegated fact and we are delegating facts, we need to change target host for them
                         if original_task.delegate_to is not None and original_task.delegate_facts: