Make QPageRanges::detach public, add data stream operators

As per QUIP-19 discussion, value types should have streaming operators,
and detach should be public.

detach() is still documented as \internal, like other public detach
methods in value types.

Change-Id: I30451909ad5226088fb05206f83983dda5b0c6b5
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

src/gui/painting/qpageranges.cpp

@@ -42,6 +42,7 @@
 
 #include <QtCore/qstack.h>
 #include <QtCore/qdebug.h>
+#include <QtCore/qdatastream.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -325,6 +326,40 @@ void QPageRanges::detach()
         d.reset(new QPageRangesPrivate);
 }
 
+#if !defined(QT_NO_DATASTREAM)
+/*!
+    \fn QDataStream &operator<<(QDataStream &stream, const QPageRanges &pageRanges)
+    \relates QPageRanges
+
+    Writes \a pageRanges to \a stream as a range string.
+
+    \sa QPageRanges::toString
+*/
+
+QDataStream &operator<<(QDataStream &s, const QPageRanges &pageRanges)
+{
+    s << pageRanges.toString();
+    return s;
+}
+
+/*!
+    \fn QDataStream &operator>>(QDataStream &stream, QPageRanges &pageRanges)
+    \relates QPageRanges
+
+    Reads a page ranges string from \a stream and stores it in \a pageRanges.
+
+    \sa QPageRanges::fromString
+*/
+
+QDataStream &operator>>(QDataStream &s, QPageRanges &pageRanges)
+{
+    QString rangesString;
+    s >> rangesString;
+    pageRanges = QPageRanges::fromString(rangesString);
+    return s;
+}
+#endif // QT_NO_DATASTREAM
+
 #ifndef QT_NO_DEBUG_STREAM
 QDebug operator<<(QDebug dbg, const QPageRanges &pageRanges)
 {

src/gui/painting/qpageranges.h

@@ -49,6 +49,7 @@
 QT_BEGIN_NAMESPACE
 
 class QDebug;
+class QDataStream;
 class QPageRangesPrivate;
 QT_DECLARE_QESDP_SPECIALIZATION_DTOR_WITH_EXPORT(QPageRangesPrivate, Q_GUI_EXPORT)
 
@@ -97,13 +98,19 @@ public:
     int firstPage() const;
     int lastPage() const;
 
+    void detach();
+
 private:
     bool isEqual(const QPageRanges &other) const noexcept;
-    void detach();
 
     QExplicitlySharedDataPointer<QPageRangesPrivate> d;
 };
 
+#ifndef QT_NO_DATASTREAM
+Q_GUI_EXPORT QDataStream &operator<<(QDataStream &, const QPageRanges &);
+Q_GUI_EXPORT QDataStream &operator>>(QDataStream &, QPageRanges &);
+#endif
+
 #ifndef QT_NO_DEBUG_STREAM
 Q_GUI_EXPORT QDebug operator<<(QDebug dbg, const QPageRanges &pageRanges);
 #endif