id-length rule does not detect all possible cases for defining identifiers

[BYK]

Forked off of #3282, specifically #3282 (comment) reported by @mysticatea

id-length rule does not support the following cases:

   {
        code: "class x { }",
        ecmaFeatures: {classes: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "class Foo { x() {} }",
        ecmaFeatures: {classes: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "function foo(x = 0) { }",
        ecmaFeatures: {defaultParams: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "function foo(...x) { }",
        ecmaFeatures: {restParams : true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "var {x} = {};",
        ecmaFeatures: {destructuring: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "var {a: [x]} = {};",
        ecmaFeatures: {destructuring: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "import x from \"x\";",
        ecmaFeatures: {modules: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "export var x = 0;",
        ecmaFeatures: {modules: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    },
    {
        code: "({a: obj.x}) = {};",
        ecmaFeatures: {destructuring: true},
        errors: [{ message: "Identifier name 'x' is too short. (< 2)", type: "Identifier"}]
    }

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[BYK]

I am working on this.

[mysticatea]

👍

[BYK]

I have an almost done patch but holding it for the ({a: obj.x}) = {}; pattern which is quite tricky to handle.