[O] BUG: org-block face not working

[Michal Koval]

Hello,

recently I switched from maint to master (release_8.3beta-1091-g96c533)
and noticed that org-block face defined in my theme does not work anymore.

What could be of some help is that when I type <s TAB, I see a code block
#+BEGIN_SRC

#+END_SRC

with the correct background face in the block specified in my theme.
But, when I type in a language (typing one non-blank character after
BEGIN_SRC is enough), the face inside the block changes to the Emacs
default one.
e.g.
#+BEGIN_SRC python

#+END_SRC

I got the same behavior with emacs -q.

Regards,

Michal