QUrlQuery: Implement initializer list constructor

[ChangeLog][QtCore][QUrlQuery] QUrlQuery now provides an
initializer list constructor. It can be created using a list of
key/value pairs.

Fixes: QTBUG-68645
Change-Id: Ief5939aa477718f6dd3580f2c60f95ff3aa892ae
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/io/qurlquery.cpp

@@ -145,6 +145,14 @@ QT_BEGIN_NAMESPACE
     \since 5.2
 */
 
+/*!
+    \fn QUrlQuery(std::initializer_list<QPair<QString, QString>> list)
+
+    \since 5.13
+
+    Constructs a QUrlQuery object from the \a list of key/value pair.
+*/
+
 typedef QList<QPair<QString, QString> > Map;
 
 class QUrlQueryPrivate : public QSharedData

src/corelib/io/qurlquery.h

@@ -48,6 +48,8 @@
 #include <QtCore/qstringlist.h>
 #endif
 
+#include <initializer_list>
+
 QT_BEGIN_NAMESPACE
 
 Q_CORE_EXPORT uint qHash(const QUrlQuery &key, uint seed = 0) Q_DECL_NOTHROW;
@@ -59,6 +61,13 @@ public:
     QUrlQuery();
     explicit QUrlQuery(const QUrl &url);
     explicit QUrlQuery(const QString &queryString);
+    QUrlQuery(std::initializer_list<QPair<QString, QString>> list)
+        : QUrlQuery()
+    {
+        for (const QPair<QString, QString> &item : list)
+            addQueryItem(item.first, item.second);
+    }
+
     QUrlQuery(const QUrlQuery &other);
     QUrlQuery &operator=(const QUrlQuery &other);
 #ifdef Q_COMPILER_RVALUE_REFS

tests/auto/corelib/io/qurlquery/tst_qurlquery.cpp

@@ -233,6 +233,14 @@ void tst_QUrlQuery::constructing()
     query += qMakePair(QString("prosent"), QString("%"));
     copy.setQueryItems(query);
     QVERIFY(!copy.isEmpty());
+
+    QUrlQuery fromList = {
+        {QString("type"), QString("login")},
+        {QString("name"), QString::fromUtf8("åge nissemannsen")},
+        {QString("ole&du"), QString::fromUtf8("anne+jørgen=sant")},
+        {QString("prosent"), QString("%")}
+    };
+    QCOMPARE(fromList, copy);
 }
 
 void tst_QUrlQuery::addRemove()