QDoc: Comments in snippets not processed correctly

If a comment is encountered in a snippet file (eg: doc/src/snippets/code/src.corelib.tools.qvector.cpp) an opening <span> tag is created, but the closing tag is not. So the following snippet (from QVector::append):

//! [7]
QVector<QString> vector(0);
vector.append("one");
vector.append("two");
vector.append("three");
// vector: ["one", "two", three"]
//! [7]

Becomes:

<pre> <a href="qvector.html">QVector</a><QString> vector(0);
vector.append(<span class="char">"one"</span>);
vector.append(<span class="char">"two"</span>);
vector.append(<span class="char">"three"</span>);
<span class="comment">// vector: [<span class="char">"one"</span>, <span class="char">"two"</span>, three<span class="char">"]</span></pre>

As you can see there is a missing </span> corresponding to the class="comment" tag and this causes weird colours in some browsers like Opera.