2.0: window.opener declared as readonly

[jeffreymorlan]

When you open a popup window of a page on a different domain, for security reasons you might want to set its window.opener to null. This is a type error in 2.0 because the opener property is incorrectly declared read-only:

var newWnd = window.open(...);
newWnd.opener = null;
// Left-hand side of assignment expression cannot be a constant or a read-only property.

[kitsonk]

It is doing this because the Microsoft Edge IDL has it as read only. Chromium as a special getter. The W3C IDL states that it is read/write and describes the behaviour of when setting it to null.

[mhegazy]

PRs welcomed. You can find more information about contributing lib.d.ts fixes at https://github.com/Microsoft/TypeScript/blob/master/CONTRIBUTING.md#contributing-libdts-fixes.