qdoc already ignores QML signal handler comments
and does not report errors for missing QML signal
handler documentation. but the test case for this
bug revealed a separate bug. The test case contains
no import statements, which, technically is legal
but probably won't happen. Still, qdoc failed to
generate output for the test case QML file because
it didn't contain an import statement before the
first qdoc comment. This was caused by an
uninitialized variable, which has now been fixed.
Task-number: QTBUG-30043
Change-Id: Iafa2087b85a6c9e354b2be86c779bbd191181218
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>