#### Support implicit declared functions and components (#18690 by @fisker)

<!-- prettier-ignore -->
```flow
// Input
declare module "foo" {
  function greet(name: string): string;
  component Button(label: string);
}

// Prettier stable
SyntaxError: Unexpected token `;`, expected the token `{` (2:39)

// Prettier main
<Same as input>
```
