Fix interaction of QQuickItems with the garbage collector

The QObject ownership of QQuickItem objects is not accessible / mutable
in QML, because the parent property maps to the (dynamic) visual parent.

There are use-cases of creating QQuickItem objects without a QObject parent and
to support this, the visual parent needs to mark its visual children in order
to provide intuitive semantics.

[ChangeLog][QtQuick][Import Behavior Changes] A QQuick Item is now strongly
referenced by its visual parent item, so it doesn't require a QObject parent to
stay alive.

Task-number: QTBUG-35913
Change-Id: Ief2d40ac76298a0cf241ca73ff654c4ecfa12748
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/tests/auto/quick/qquickitem/data/visualParentOwnership.qml b/tests/auto/quick/qquickitem/data/visualParentOwnership.qml
new file mode 100644
index 0000000000..644d14ba43
--- /dev/null
+++ b/tests/auto/quick/qquickitem/data/visualParentOwnership.qml
@@ -0,0 +1,14 @@
+import QtQuick 2.0
+
+Item {
+    Component {
+        id: factory
+        Item {}
+    }
+
+    property Item keepAliveProperty;
+
+    function createItemWithoutParent() {
+        return factory.createObject(/*parent*/ null);
+    }
+}