Description of problem:
If you have a program listing between two paragraphs, the spacing is not uneven.  There is less space after the a program listing than after a paragraph.  This looks odd.  I can only definitively see this in html because I can use an inspector to view the CSS values.  PDF I am not sure about completely, but it does look strange if an admonition follows a program listing.  


Example:

<para>para 1</para>
<programlisting>listing 1</programlisting>
<para>para 2</para>
<programlisting>listing 2</programlisting>
  
Actual results:
In the HTML output there is less space between the listing and the 2nd paragraph than the 1st paragraph and the listing.

Expected results:

The paragraphs and program listings are evenly spaced.

Additional info:

This seems to be fixable in html by changing common.css, so there is the same margin after pre blocks as others.

from 

      pre {
         margin-bottom: 0.3em;
      }

to 

      pre {
         margin-bottom: 1em;
      }