QmlJS: Abort if file could not be opened

Change-Id: Ic2175c2b8dc6ec8ce378db07bdd2b667b15f70cb
Reviewed-by: Marco Benelli <marco.benelli@qt.io>

src/libs/qmljs/qmljsmodelmanagerinterface.cpp

@@ -782,7 +782,8 @@ static bool findNewQmlLibraryInPath(const QString &path,
     }
 
     // found a new library!
-    qmldirFile.open(QFile::ReadOnly);
+    if (!qmldirFile.open(QFile::ReadOnly))
+        return false;
     QString qmldirData = QString::fromUtf8(qmldirFile.readAll());
 
     QmlDirParser qmldirParser;