Fix with loop + delegate issues

* Don't re-use the existing connection if the remote_addr field of
  the play context has changed
* When overriding variables in PlayContext (from task/variables),
  don't set the same attribute based on a different variable name
  if we had already previously set it from another variable name

Fixes #13880

lib/ansible/executor/task_executor.py

@@ -367,7 +367,7 @@ class TaskExecutor:
                 self._task.args = variable_params
 
         # get the connection and the handler for this execution
-        if not self._connection or not getattr(self._connection, 'connected', False):
+        if not self._connection or not getattr(self._connection, 'connected', False) or self._play_context.remote_addr != self._connection._play_context.remote_addr:
             self._connection = self._get_connection(variables=variables, templar=templar)
             self._connection.set_host_overrides(host=self._host)
         else:

lib/ansible/playbook/play_context.py

@@ -366,12 +366,17 @@ class PlayContext(Base):
         else:
             delegated_vars = dict()
 
+        attrs_considered = []
         for (attr, variable_names) in iteritems(MAGIC_VARIABLE_MAPPING):
             for variable_name in variable_names:
+                if attr in attrs_considered:
+                    continue
                 if isinstance(delegated_vars, dict) and variable_name in delegated_vars:
                     setattr(new_info, attr, delegated_vars[variable_name])
+                    attrs_considered.append(attr)
                 elif variable_name in variables:
                     setattr(new_info, attr, variables[variable_name])
+                    attrs_considered.append(attr)
 
         # make sure we get port defaults if needed
         if new_info.port is None and C.DEFAULT_REMOTE_PORT is not None: