Replace this in object methods

[SarahIsWeird]

Adds the functionality from #181.

Here's my test script, feel free to try to break it some more :)

export default () => {
    const foo = {
        a() {
            this.b = 1
        }
    };

    class MyClass {
        field = {
            a() {
                this.b = 1
            }
        }

        foo() {
            return {
                a() {
                    this.b = 1
                }
            }
        }
    }

    const iTakeAnObjectArgument = ({ a }) => {
        a()
    }

    iTakeAnObjectArgument({
        a() {
            this.b = 1
        }
    })

    let hello = {
        a() {
            this.b = 1
        }
    }

    const bye = hello
    hello = ':('

    return {
        foo,
        bar: {
            a() {
                this.b = 1
            }
        },
        baz: () => ({
            a() {
                this.b = 1
            }
        }),
        thingy: (() => ({
            a() {
                this.b = 1
            }
        }))(),
        whatever: function () {
            return {
                a() {
                    this.b = 1
                }
            }
        },
        MyClass,
        hello,
        bye,
    };
};