Fix crash when using signal handlers on group properties

This is a regression introduced with commmit
49a11e882059ee1729f776722e085dd21d378c36: The typeRef can be null.

I found this when testing grouped properties and property revisions.

<TestComponent.qml>
import QtQuick 2.0

Item {
    property alias textEdit: textEdit

    TextEdit {
        id: textEdit
    }
}

import QtQuick 2.8

Item {
    TestComponent {
        textEdit.onEditingFinished: console.log("test")
    }
}

Instead of an error message, this crashes without this patch.
This is a regression introduced by using QQmlType by value.

Change-Id: Ib18a0ad878f7c4696c22bc65fee636b84b966f03
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/qml/compiler/qqmltypecompiler.cpp b/src/qml/compiler/qqmltypecompiler.cpp
index eeb5595a9a..fab865081a 100644
--- a/src/qml/compiler/qqmltypecompiler.cpp
+++ b/src/qml/compiler/qqmltypecompiler.cpp
@@ -412,7 +412,7 @@ bool SignalHandlerConverter::convertSignalHandlerExpressionsToFunctionDeclaratio
                 const QString &originalPropertyName = stringAt(binding->propertyNameIndex);
 
                 auto *typeRef = resolvedTypes.value(obj->inheritedTypeNameIndex);
-                const QQmlType type = typeRef->type;
+                const QQmlType type = typeRef ? typeRef->type : QQmlType();
                 if (type.isValid()) {
                     COMPILE_EXCEPTION(binding, tr("\"%1.%2\" is not available in %3 %4.%5.").arg(typeName).arg(originalPropertyName).arg(type.module()).arg(type.majorVersion()).arg(type.minorVersion()));
                 } else {