Not work with multilanguage wiki

When creating a change request on a translated page it always get a conflict because it try to merge it with the page of the original language. 

How to reproduce:

1. Have a multilanguage wiki.
2. Create a page in standard language
3. Translate this page to another langage.
4. Create a change request on the translated page.

What happens:

• You receive a conflict because it try to merge it with the page of the original language.
  

• Language of the page is not considered in the change request.

What should happen:

• It should try to merge with the page of the same language.