I ran into this with some code I'm writing which checks against 
`lexical-binding'.
Should the following result in "lexical binding enabled" or 
"lexical binding disabled"?:

#+begin_src emacs-lisp :lexical t
(message "lexical binding %sabled" (if lexical-binding "en" 
"dis"))
#+end_src

Currently the `lexical-binding' variable is not bound because 
`org-babel-execute:emacs-lisp'
passes t to `eval', which enables lexical binding, but does not 
bind the `lexical-binding' variable.
The attached patch binds the variable in the lexical environment.
It's a matter of whether or not this is the right thing to do.
Thoughts?


Emacs  : GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, X 
toolkit, cairo version 1.17.4, Xaw3d scroll bars)
 of 2021-09-04
Package: Org mode version 9.4.6 (9.4.6-ga451f9 @ 
/home/n/.emacs.d/straight/build/org/)