Optimize ExecutionEngine::metaTypeToJS()

We almost never need to construct a QVariant to do this. Constructing a
QVariant is excessively expensive if you have something simple like an
integer. This also fixes the unexpected "unwrapping" of variants when we
pass them through QJSValue.

[ChangeLog][QtQml][Important Behavior Changes] If you create a QJSValue
from a nested QVariant (that is, a QVariant containing another
QVariant), then, when retrieving its contents again, the outer variant
is not unwrapped anymore. Rather, you get exactly the value you've
passed in.

Change-Id: I8c16eed4f13e8cfdeced0756eef593b3b8e84dd1
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 3 insertions, 1 deletions

diff --git a/src/qml/jsruntime/qv4sequenceobject_p.h b/src/qml/jsruntime/qv4sequenceobject_p.h
index 9143430872..603d33d6d8 100644
--- a/src/qml/jsruntime/qv4sequenceobject_p.h
+++ b/src/qml/jsruntime/qv4sequenceobject_p.h
@@ -80,7 +80,9 @@ struct Q_QML_PRIVATE_EXPORT SequencePrototype : public QV4::Object
     static ReturnedValue method_sort(const FunctionObject *, const Value *thisObject, const Value *argv, int argc);
 
     static ReturnedValue newSequence(QV4::ExecutionEngine *engine, int sequenceTypeId, QObject *object, int propertyIndex, bool readOnly, bool *succeeded);
-    static ReturnedValue fromVariant(QV4::ExecutionEngine *engine, const QVariant& v, bool *succeeded);
+    static ReturnedValue fromVariant(QV4::ExecutionEngine *engine, const QVariant &v, bool *succeeded);
+    static ReturnedValue fromData(QV4::ExecutionEngine *engine, const QMetaType &type, const void *data, bool *succeeded);
+
     static int metaTypeForSequence(const Object *object);
     static QVariant toVariant(Object *object);
     static QVariant toVariant(const Value &array, int typeHint, bool *succeeded);