QmlJSEditor: warn when editing .ui.qml, activate designer checks

Change-Id: I2f6d39633341bd1197d16c5c097573d4ab090896
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@digia.com>
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>

src/plugins/qmljseditor/qmljseditor.h

@@ -135,6 +135,8 @@ private:
     int m_oldCursorPosition;
 
     FindReferences *m_findReferences;
+
+    bool m_firstSementicInfo;
 };