QmlDesigner: Fix bug in MetaInfoReader

Hints were never cleared.

Change-Id: I9c60314f8c345de487c8ddf0b7f1085d6e496a32
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/qmldesigner/designercore/metainfo/metainforeader.cpp

@@ -154,6 +154,7 @@ MetaInfoReader::ParserSate MetaInfoReader::readMetaInfoRootElement(const QString
     if (name == typeElementName) {
         m_currentClassName.clear();
         m_currentIcon.clear();
+        m_currentHints.clear();
         return ParsingType;
     } else {
         addErrorInvalidType(name);