String Concealing breaks class constructor

[MichaelXF]

Describe the bug:

String Concealing breaks class constructor

Config and Small code sample

Config:

{
  target: "node",
  stringConcealing: true
}

Code:

class MyClass1 {}
class MyClass2 extends MyClass1 {
  constructor(){
    super();
    this["string1"] = true;
    this["string2"] = true;
    this["string3"] = true;
  }
}

var instance = new MyClass2();

Error:

(node:16224) UnhandledPromiseRejectionWarning: ReferenceError: Must call super constructor in derived class before accessing 'this' or returning from derived constructor