changed callbacks are not all triggered when aliasing properties

[hunger]

Bug Description

When running the code below, I get this output:

Incrementing test-value in Demo
Inner: test-value CHANGED

I would expect all changed signals to fire as all the values have changed. It should IMHO not matter that they are all aliased together and technically only one of them exists.

Reproducible Code (if applicable)

import { Button } from "std-widgets.slint";

component Inner inherits HorizontalLayout {
    in-out property <int> test-value;

    changed test-value => {
        debug("Inner: test-value CHANGED")
    }

    Rectangle {
        background: red;
        height: 50px;
        width: 50px;
    }
}

component Intermediate inherits HorizontalLayout {
    in-out property <int> test-value;

    changed test-value => {
        debug("Intermediate: test-value CHANGED")
    }

    Inner {
        test-value <=> root.test-value;
    }
}

export component Demo {
    property <int> test-value: 42;

    changed test-value => {
        debug("Demo: test-value CHANGED")
    }

    VerticalLayout {
        Button {
            text: "Click me";
            clicked => {
                debug("Incrementing test-value in Demo");
                root.test-value += 1;
            }
        }

        Intermediate {
            test-value <=> root.test-value;
        }
    }
}

Environment Details

• Slint Version: master
• Platform/OS: Linux
• Programming Language: Slint
• Backend/Renderer: Slintpad

Product Impact

No response

[ogoffart]

I think this is a bug in how the remove_alias pass not merge the changed event as it should.

Another possible similar report in #7781