Attempt to fix the `Array.prototype.includes` and `String.prototype.includes` polyfills (issue 9514, 9516)
Attempt to fix the `Array.prototype.includes` and `String.prototype.includes` polyfills (issue 9514, 9516)

I don't understand why the previous way importing the polyfills didn't work, and I don't have time to try and figure it out, however this patch seems to fix things.

Fixes 9514.
Fixes 9516.

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