Deprecate Qt::WFlags.

It seems to date from the Qt 1 days, and such abbreviations
are not current Qt style.

Change-Id: Iea7259bd7ba78b2c0863e3f6675e10826712ffd9
Reviewed-by: Andy Shaw <andy.shaw@digia.com>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>

src/corelib/global/qnamespace.h

@@ -1410,7 +1410,9 @@ public:
     Q_DECLARE_FLAGS(MatchFlags, MatchFlag)
 
     typedef void * HANDLE;
+#if QT_DEPRECATED_SINCE(5, 0)
     typedef WindowFlags WFlags;
+#endif
 
     enum WindowModality {
         NonModal,

src/corelib/global/qnamespace.qdoc

@@ -1863,6 +1863,8 @@
 
 /*!
     \typedef Qt::WFlags
+    \obsolete
+    This typedef is obsolete. Use Qt::WindowFlags instead.
 
     Synonym for Qt::WindowFlags.
 */