[FIX] website_forum: Manual forward port from 30a6be0 and 0de1d89

Code has been refactored since 8.0

addons/website_forum/models/forum.py

@@ -320,6 +320,17 @@ class Post(models.Model):
             self.env.user.sudo().add_karma(post.forum_id.karma_gen_question_new)
         return post
 
+    @api.multi
+    @api.depends('name', 'post_type')
+    def name_get(self):
+        result = []
+        for post in self:
+            if post.post_type == 'discussion' and post.parent_id and not post.name:
+                result.append((post.id, '%s (%s)' % (post.parent_id.name, post.id)))
+            else:
+                result.append((post.id, '%s' % (post.name)))
+        return result
+
     @api.multi
     def write(self, vals):
         if 'content' in vals:

addons/website_forum/views/website_forum.xml

@@ -727,7 +727,10 @@
                     t-field="answer.create_uid"
                     t-field-options='{"widget": "contact", "country_image": true, "fields": ["name", "country_id"]}'
                     style="display: inline-block;"/>
-                <div class="text-muted">On <span t-field="answer.create_date" t-field-options='{"format":"short"}'/></div>
+                <div class="text-muted">
+                    <a t-attf-href="/forum/#{slug(question.forum_id)}/question/#{slug(question)}#answer_#{answer.id}">On</a> 
+                    <span t-field="answer.create_date" t-field-options='{"format":"short"}'/>
+                </div>
             </div>
             <div class="clearfix"><span t-field="answer.content" class="oe_no_empty"/></div>
             <div class="clearfix">