`@callback` is only generic after `@template` tag

TypeScript Version: master

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Code

Our declaration:

export interface JSDocSignature extends JSDocType, Declaration {
    kind: SyntaxKind.JSDocSignature;
    typeParameters?: ReadonlyArray<JSDocTemplateTag>;
    ...
}

Attempt to use:

/**
 * @callback Cb
 * @template T
 * @param {T} p
 * @return {T}
 */

/** @type {Cb} */
const x = p => p;

Expected behavior:

typeParameters is set somewhere, and type Cb = <T>(p: T) => T (or type Cb<T> = (p: T) => T)

Actual behavior:

1. typeParameters is not set.
2. Cb says that it requires a generic argument, but when provided, there's an error on x: 'any => any' isn't assignable to 'Cb'.
3. Requesting quickinfo on Cb/**/<number> causes an infinite recursion in getTypePredicateOfSignature.

Also: DeclarationWithTypeParameters includes JSDocCallbackTag, but that does not include a declaration for typeParameters -- and yet it works if I move the @template tag one line up!