Uncaught implicit any for computed property in destructure

[ghost]

TypeScript Version: 3.1.0-dev.20180810

Code

let x: boolean;
({ ["a" + "b"]: x } = 0);
x = 0["a" + "b"];

Expected behavior:

Error on both lines.

Actual behavior:

Error only on 0["a" + "b"].

[ghost]

This happens because getTextOfPropertyName, used by checkObjectLiteralDestructuringPropertyAssignment, returns undefined for computed properties and we don't handle that correctly. So this is another bug due to #18217.