Signature help not select correct overload for partially completed function #33328

From microsoft/vscode#80570

TypeScript Version: 3.7.0-dev.20190907

Search Terms:

• SignatureHelp
• parameter hints

Code
For the code

declare function addEventHandler(event: "onPlayerJoin", x: number): void;
declare function addEventHandler(event: "onPlayerQuit", y: string): void;

addEventHandler('onPlayerQuit')

1. Trigger signature help after the closing ' in the call to addEventHandler

Expected behavior:
Signature help for the second overload is returned

Actual behavior:
Signature help for both overloads is returned. We end up showing the one for onPlayerJoin first