All pages with class definitions with async_context properties are potentially updated at each startup

Steps reproduce, for the example class XWiki.UIExtensionClass:

1. Have an instance with the standard flavor installed
2. The page XWiki.UIExtensionClass is created when the wiki is accessed for the first time / installed from DW
3. go to administration & set the language of the wiki to 'fr'
4. stop the wiki
5. start the wiki
6. access any page from the browser

Expected result:

• there is no impact on the XWiki.UIExtensionClass class

Actual result:

• a new version is added in the history of the XWiki.UIExtensionClass class, with message "Synchronisé les définitions de propriété de classe obligatoire aux valeurs par défaut"

The comparison shows that the differences are that the labels of the values of the static list async_context are updated to the current language of the context:

Important note: when the wiki is multilanguage (set to multilanguage in the step 3 above), this class may be updated at each restart of the wiki, depending on the context language of the first request to the wiki. Thus, these updates may endup looping and changing from one to another continuously, filling in the history of these pages needlessly, without any language being actually more relevant than another because the wiki is multilanguage:

Impacted classes include (I didn't check all the classes, there may be others):

• XWiki.UIExtensionClass
• Panels.PanelClass
• XWiki.WikiMacroClass
• XWiki.DocumentAsyncClass