[O] Babel CALL no longer produces HTML output

[Jarmo Hurri]

Greetings.

The Org example below used to work correctly when exported as HTML until
I pulled a newer version of Org from git. I am first going to include
the example here, and then explain the reasoning behind its structure.

=======================================================================
* Example
  
  This call here produced HTML output when exported as HTML until the
  newer versions of Org. Now it produces no HTML output whatsoever.

  #+CALL: rekursio-pystyviivat[:noweb yes]() :results html
  
  The following code blocks still work as expected.
  
  #+NAME: rekursio-pystyviivat-runko
  #+BEGIN_SRC processing :exports none
    if (viivoja == 0)
    return;

    line (x, 0, x, korkeus);
    piirraPystyviivat (viivoja - 1, x + 10, 0.9 * korkeus);
  #+END_SRC

  #+NAME: rekursio-pystyviivat
  #+BEGIN_SRC processing :exports code :noweb no
    void piirraPystyviivat (int viivoja, float x, float korkeus)
    {
      <<rekursio-pystyviivat-runko>>
    }

    void setup ()
    {
      size (600, 400);
      noLoop ();
    }

    void draw ()
    {
      piirraPystyviivat (50, 10, 350);
    }
  #+END_SRC
=======================================================================

In the example above I am playing with noweb to produce the following
_excellent_ teaching effect:

- the last Babel code block is what a student sees

- the student is supposed to replace
  <<rekursio-pystyviivat-runko>>
  with correct code, in this case the body of a recursive function

- the last block has ":noweb no" so that the missing part is not
  replaced by the correct solution

- in the CALL, however, noweb is set to yes so that noweb replacement is
  done, and the first block produces the correct output (in the case of
  Processing language, this is a picture)

I use this structure quite a bit in my material, which is finished
except for layout formatting. So I am going to be in trouble if I can no
longer get the logic to work in Org.

Jarmo