Refactor to extract existing function to outer scope

**TypeScript Version:** 3.1.0-dev.20180813 **Code** ```ts function a(x: number) { function b(y: number) { return x + y; } return b(1); } ``` **Expected behavior:** Refactor on `b` to convert to: ```ts function a(x: number) { return b(1, x); } function b(y: number, x: number) { return x + y; } ``` **Actual behavior:** No such refactor. We already have the ability to refactor *code* to an outer scope. So a workaround is to highlight the entire body of `b` and refactor to a function in global scope, then delete `b` and rename the refactored function to `b`, then manually update call sites.