Qbs: Fallback to filename as project name if qbs parsing fails

Use the project filename as a fallback in case qbs parsing fails
without being able to extract the main project data.

Task-number: QTCREATORBUG-9777
Change-Id: Iceedf55c7f5d56a8876c19bcbd94082752c08336
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/qbsprojectmanager/qbsnodes.cpp

@@ -624,7 +624,10 @@ void QbsProjectNode::update(const qbs::ProjectData &prjData)
         }
     }
 
+    if (!prjData.name().isEmpty())
         setDisplayName(prjData.name());
+    else
+        setDisplayName(m_project->displayName());
 
     removeProjectNodes(toRemove);
     addProjectNodes(toAdd);