'__GeneratorFunction()' visible on globalThis

[rbri]

The last refactroings leaking the '__GeneratorFunction()' into the properties of the globalThis object

(found while using the current head (277cf99) in HtmlUnit)

Test case:

@Test
public void todo() {
    final String script =
            "var all = [];" +
            "for (var property in this) {" +
            "  if (typeof this[property] == 'function') {" +
            "    all.push(property + '()');" +
            "  } else {" +
            "    all.push(property);" +
            "  }" +
            "}" +
            "all.sort();" +
            "all.join()";

    Utils.runWithAllModes(
        Utils.contextFactoryWithFeatures(),
        cx -> {
            TopLevel scope = cx.initSafeStandardObjects();

            Object result = cx.evaluateString(scope, script, "test_script", 1, null);
            assertEquals("__GeneratorFunction(),all,global,property", result);  // this is wrong __GeneratorFunction() should not be visible here
            return null;
        });
}

[rbri]

@aardvark179 this is the only regression i found so far with all your stuff. Great!

[aardvark179]

So this happened while sorting general creation of built ins. Ideally we would create the built ins as BuiltIns on TopLevel and then set the public names from those, but we're not quite there yet. I have a later commit that will turn that property key into a symbol rather than a string, but that's still not perfect.

[rbri]

fixed it in core-js during the window setup - so this is not urgent