made display part of variable manager and corrected reference to it

fixes #12859

lib/ansible/vars/__init__.py

@@ -49,13 +49,6 @@ from ansible.vars.unsafe_proxy import wrap_var
 VARIABLE_CACHE = dict()
 HOSTVARS_CACHE = dict()
 
-try:
-    from __main__ import display
-    display = display
-except ImportError:
-    from ansible.utils.display import Display
-    display = Display()
-
 def preprocess_vars(a):
     '''
     Ensures that vars contained in the parameter passed in are
@@ -89,6 +82,13 @@ class VariableManager:
         self._inventory = None
         self._omit_token = '__omit_place_holder__%s' % sha1(os.urandom(64)).hexdigest()
 
+        try:
+            from __main__ import display
+            self._display = display
+        except ImportError:
+            from ansible.utils.display import Display
+            self._display = Display()
+
     def __getstate__(self):
         data = dict(
             fact_cache = self._fact_cache.copy(),
@@ -291,7 +291,7 @@ class VariableManager:
                     else:
                         # we do not have a full context here, and the missing variable could be
                         # because of that, so just show a warning and continue
-                        display.vvv("skipping vars_file '%s' due to an undefined variable" % vars_file_item)
+                        self._display.vvv("skipping vars_file '%s' due to an undefined variable" % vars_file_item)
                         continue
 
             if not C.DEFAULT_PRIVATE_ROLE_VARS: