Improvements for option freeze

[valueof]

New options freeze landed with #1276. This bug is about general improvements we can make to it. Feel free to add your own.

• Can we re-use lists of variables from vars.js instead of having yet another list within the source code?
• Should we add checks for Array.isArray etc?

[caitp]

The lists in vars.js look good in some ways, but they would still need to be filtered. For instance, we don't really care about modifying the global context for this warning. Then again, I suppose it wouldn't matter unless an expression contained window.prototype.foo or whatever, though.

Another improvement could be to also check for assignments to the deprecated __proto__ property.

[WanderingZombie]

"Bad option freeze" is raised on standard jQuery $(document).ready(function () {});

[valueof]

@WanderingZombie This means you're using old version of JSHint.

[kangax]

Should we add checks for Array.isArray etc?

I think we should.

Can we re-use lists of variables from vars.js instead of having yet another list within the source code?

Any of ecmaIdentifiers seem fine. Optionally, we could make a distinction between native, ES-defined objects (Array, String, Object, etc.) and browser built-ins (alert, Audio, Blob, CanvasPattern, etc.).

Perhaps freeze: {native | browser} or even freeze: { native | dom | bom } (but not sure if that kind of granularity is needed).