Bug? org-export-babel-evaluate setting breaks :exports results

[William Denton <wtd@pobox.com>]

I'm working on a big Org file on a slow machine, so I set 
org-export-babel-evaluate to nil so exporting to PDF just generates the file 
from what's in the buffer, without doing any calculating.

I have a mix of source blocks, and all of a sudden the code began to appear in 
the PDF when all I wanted were the results.  I boiled it down to the example 
below.  If you save that to a file, load it, ~C-c C-e l o RET~ to export to PDF, 
you will see the ls command and the output, even though the setting is ":exports 
results".

Now delete the org-export-babel-evaluate line, ~C-x C-v RET~ to reload the 
file and pick up the new setting, then export to PDF.  You will not see the ls 
command, just the output.

###### BEGIN
# -*- org-export-babel-evaluate: nil -*-

#+BEGIN_SRC shell :results value :exports results
ls /etc | wc -l
#+END_SRC

#+RESULTS:
: 307
###### END

I'm not sure what's happening, but it seems like a bug.

(This is on Emacs 25.2.50.2 with Org compiled from source today, up to 
Nicolas's 2b22d503e1ee83f3a2681964f9de8405438a6385 commit yesterday).

Bill
-- 
William Denton :: Toronto, Canada :: https://www.miskatonic.org/
Caveat lector.