Adpat to changes in QAbstractFileEngine/Iterator in qtbase

- Replace hasNext()/next() with a `bool advance()` method
- Replace QAFE::FileTime with QFile::FileTime, they are identical
- QAFE methods now return std::unique_ptr, which matches reality as call
  sites stored the pointers in a std::unique_ptr anyway

FileIteratorWrapper:
State::BaseIteratorEnd is only needed when using hasNext()/next(),
hasNext() changes m_status to State::BaseIteratorEnd, then next() checks
that and changes m_status to State::Ended; this isn't needed with
advance() since it's only one method.

Change-Id: I4414f334715237a2fc13ace6f4733d975e2cfaa3
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>
(cherry picked from commit ba3f0bc841)

src/tools/qml2puppet/qmlprivategate/qmlprivategate.cpp

@@ -473,16 +473,25 @@ ComponentCompleteDisabler::~ComponentCompleteDisabler()
 class QrcEngineHandler : public QAbstractFileEngineHandler
 {
 public:
+#if QT_VERSION >= QT_VERSION_CHECK(6, 8, 0)
+    std::unique_ptr<QAbstractFileEngine> create(const QString &fileName) const final;
+#else
     QAbstractFileEngine *create(const QString &fileName) const final;
+#endif
 };
 
-QAbstractFileEngine *QrcEngineHandler::create(const QString &fileName) const
+#if QT_VERSION >= QT_VERSION_CHECK(6, 8, 0)
+std::unique_ptr<QAbstractFileEngine>
+#else
+QAbstractFileEngine *
+#endif
+QrcEngineHandler::create(const QString &fileName) const
 {
     if (fileName.startsWith(":/qt-project.org"))
-        return nullptr;
+        return {};
 
     if (fileName.startsWith(":/qtquickplugin"))
-        return nullptr;
+        return {};
 
     if (fileName.startsWith(":/")) {
         const QStringList searchPaths = qmlDesignerRCPath().split(';');
@@ -493,18 +502,22 @@ QAbstractFileEngine *QrcEngineHandler::create(const QString &fileName) const
                 fixedPath.replace(":" + qrcDefintion.first(), qrcDefintion.last() + '/');
 
                 if (fileName == fixedPath)
-                    return nullptr;
+                    return {};
 
                 if (QFileInfo::exists(fixedPath)) {
                     fixedPath.replace("//", "/");
                     fixedPath.replace('\\', '/');
+#if QT_VERSION >= QT_VERSION_CHECK(6, 8, 0)
+                    return std::make_unique<QFSFileEngine>(fixedPath);
+#else
                     return new QFSFileEngine(fixedPath);
+#endif
                 }
             }
         }
     }
 
-    return nullptr;
+    return {};
 }
 
 static QrcEngineHandler* s_qrcEngineHandler = nullptr;