he flag in the related test file to see if it is
functioning as expected, DECLARE it in the <code>foo_test.cc</code>
file.

<p>If the flag does span multiple files, DECLARE it in the associated
<code>.h</code> file, and make others <code>#include</code> that
<code>.h</code> file if they want to access the flag.  The
<code>#include</code> will make explicit the dependency between the
two files. This causes the flag to be a global variable.</p>


<h2> <A name=validate>RegisterFlagValidator: Sanity-checking Fl