`Map<Integer, WhatEver> x` produces field with `string` key instead of `number` key

[atsu85]

Generating TypeScript from

class Bug {
  Map<Integer, String> intKeyMap;
}

produces

export interface Bug {
    intKeyMap: { [key: string ]: string;};
  // intKeyMap: { [key: number]: string;}; // <-- EXPECTED
}

but expecting number to be the key instead of string

[crummy]

I think objects in JS always are keyed by string.