Fix proxied clip cannot be dragged from monitor to timeline.

Fixes #1052

src/mltcontroller/clipcontroller.cpp

@@ -437,9 +437,9 @@ int ClipController::getFramePlaytime() const
     }
     if (!m_hasLimitedDuration) {
         int playtime = m_masterProducer->time_to_frames(m_masterProducer->get("kdenlive:duration"));
-        return playtime == 0 ? m_masterProducer->get_playtime() : playtime;
+        return playtime == 0 ? m_masterProducer->get_length() : playtime;
     }
-    return m_masterProducer->get_playtime();
+    return m_masterProducer->get_length();
 }
 
 QString ClipController::getProducerProperty(const QString &name) const