CryptoKey objects are deeply mutable

[ChALkeR]

> cryptoKey
CryptoKey {
  type: 'secret',
  extractable: true,
  algorithm: { name: 'AES-GCM', length: 256 },
  usages: [ 'encrypt', 'decrypt', 'encrypt' ]
}
> cryptoKey.algorithm.length = 128
> cryptoKey.algorithm.name = 'FooBar'
> cryptoKey.algorithm.x = 10
> cryptoKey.algorithm
{ name: 'FooBar', length: 128, x: 10 }

Same with usages:

> cryptoKey.usages.push('foo')
4
> cryptoKey.usages
[ 'encrypt', 'decrypt', 'encrypt', 'foo' ]

(again, auto-detected by the scanner behind @deepview-autofix)

[ChALkeR]

Ok, same in Safari, will recheck wpt.