Return type annotations ignored with recursive closures using JSDoc

<!-- 🚨 STOP 🚨 𝗦𝗧𝗢𝗣 🚨 𝑺𝑻𝑶𝑷 🚨 Half of all issues filed here are duplicates, answered in the FAQ, or not appropriate for the bug tracker. Even if you think you've found a *bug*, please read the FAQ first, especially the Common "Bugs" That Aren't Bugs section! Please help us by doing the following steps before logging an issue: * Search: https://github.com/Microsoft/TypeScript/search?type=Issues * Read the FAQ: https://github.com/Microsoft/TypeScript/wiki/FAQ Please fill in the *entire* template below. --> <!-- Please try to reproduce the issue with `typescript@next`. It may have already been fixed. --> **TypeScript Version:** 3.5.1 <!-- Search terms you tried before logging this (so others can find this issue more easily) --> **Search Terms:** - "implicit any type" - "circular reference" - "jsdoc" - "recursive" - "closure" **Code** I have a fairly complex use case in a project which uses vanilla JS with type annotations in JSDoc comments. The long and the short is that there is a function which returns a function, which may recursively call itself and will reassign some closure variables. Here is a silly example which gets the point across and demonstrates the same issue: ```js /** * @returns {function(): number} */ function circular() { let rand = Math.random(); return /** @type {function(): number} */ (function tryAgain() { if (rand < 0.5) { return rand; } rand = Math.random(); return tryAgain(); }); } ``` **Expected behavior:** TypeScript should know that the return type of `tryAgain` is a number. **Actual behavior:** When run with: ```bash tsc --allowJs --checkJs --noEmit --strict --target ES2017 *.js ``` The following error is thrown: ``` error TS7023: 'tryAgain' implicitly has return type 'any' because it does not have a return type annotation and is referenced directly or indirectly in one of its return expressions. ``` At the very least, this error seems pretty erroneous. The `tryAgain` function has _two_ return ty…