[no-invalid-this] False positive when using this to declare an attribute

[flowstate247]

Repro

{
  "rules": {
    "@typescript-eslint/no-invalid-this": ["warn"]
  }
}

class Example1 {
  i = 0
  inc(): void { this.i++ }
  alias = this.inc // Warning here
}

class Example2 {
  i = 0
  constructor() { this.alias = this.inc	}
  inc(): void { this.i++ }
  alias: () => void
}

Expected Result
No warning shown

Actual Result
Show warning "Unexpected 'this'" in the Example1 class

Additional Info
Example1 and Example2 classes are both valid TypeScript and generate identical JavaScript code.

Versions

package	version
@typescript-eslint/eslint-plugin	3.7.0
@typescript-eslint/parser	3.7.0
TypeScript	3.9.7
ESLint	7.5.0
node	v14.1.0
npm	6.14.4

[bradzacher]

#491