[IMP] *: correctly read/write website_published

The `website_published` field from the website's mixins is basically a readonly
from `is_published` field.
On read, this field will simply read `is_published` and check if the record's
website_id is accessible (only for the multi mixin).
On write, it will always write on `is_published`.

This commit improves a few things:
- A lot of code was writting on website_published which was just then writting
  on is_published. Writting directly on is_published makes more sense.
- Some backend fields would still reference `website_published` instead of
  `is_published` which would just go through the related for no reason.
  Plus, using `is_published` will make the field tooltip more accurate as we
  are not in a website context ('Visible on current website' to 'Is Published')
- Filter and search on tree view were still using the `website_published`
  related field, which is just a readonly when we are not in a frontend
  context.
- Some create and write function would have security check on
  `website_published` value but that was wrong as the user could bypass that by
  simply writting on `is_published`. For the write method, check `is_published`
  is more accurate as it will cover both case since `website_published` will
  then call the write method on `is_published`

1 files changed, 4 insertions, 3 deletions

diff --git a/addons/website_blog/models/website_blog.py b/addons/website_blog/models/website_blog.py
index 6bf40b32f63..6ec13d08370 100644
--- a/addons/website_blog/models/website_blog.py
+++ b/addons/website_blog/models/website_blog.py
@@ -194,7 +194,7 @@ class BlogPost(models.Model):
                 blog_post._write(dict(post_date=blog_post.create_date)) # dont trigger inverse function
 
     def _check_for_publication(self, vals):
-        if vals.get('website_published'):
+        if vals.get('is_published'):
             for post in self:
                 post.blog_id.message_post_with_view(
                     'website_blog.blog_post_template_new_post',
@@ -214,9 +214,10 @@ class BlogPost(models.Model):
         result = True
         for post in self:
             copy_vals = dict(vals)
-            if ('website_published' in vals and 'published_date' not in vals and
+            published_in_vals = set(vals.keys()) & {'is_published', 'website_published'}
+            if (published_in_vals and 'published_date' not in vals and
                     (not post.published_date or post.published_date <= fields.Datetime.now())):
-                copy_vals['published_date'] = vals['website_published'] and fields.Datetime.now() or False
+                copy_vals['published_date'] = vals[list(published_in_vals)[0]] and fields.Datetime.now() or False
             result &= super(BlogPost, self).write(copy_vals)
         self._check_for_publication(vals)
         return result