[FIX] website_forum, website_slides: correctly check if is admin

Before this commit and since 2f7c03d9ca, the admin user has not ID=1
anymore.

Thus, some old condition were not doing what they were expected to.

Firstly, the admin was not considered as such on the forum, and if its karma
points were not high enough, it would not be possible to do anything for the
admin. Note that it was fixed in saas-12.1 with 1dac413130

Secondly, some _search functions would not return a truthy value anymore.

closes odoo/odoo#33359

Signed-off-by: Jérémy Kersten (jke) <jke@openerp.com>

addons/website_forum/models/forum.py

@@ -288,10 +288,11 @@ class Post(models.Model):
             operator = operator == "=" and '!=' or '='
             value = True
 
-        if self._uid == SUPERUSER_ID:
+        user = self.env.user
+        # Won't impact sitemap, search() in converter is forced as public user
+        if user._is_admin():
             return [(1, '=', 1)]
 
-        user = self.env['res.users'].browse(self._uid)
         req = """
             SELECT p.id
             FROM forum_post p
@@ -379,7 +380,7 @@ class Post(models.Model):
     @api.multi
     def _get_post_karma_rights(self):
         user = self.env.user
-        is_admin = user.id == SUPERUSER_ID
+        is_admin = user._is_admin()
         # sudoed recordset instead of individual posts so values can be
         # prefetched in bulk
         for post, post_sudo in pycompat.izip(self, self.sudo()):

addons/website_slides/models/slides.py

@@ -121,7 +121,8 @@ class Channel(models.Model):
         if not value:
             operator = operator == "=" and '!=' or '='
 
-        if self._uid == SUPERUSER_ID:
+        # Won't impact sitemap, search() in converter is forced as public user
+        if self.env.user._is_admin():
             return [(1, '=', 1)]
 
         # Better perfs to split request and use inner join that left join