@internal JSDoc missing syntax highlighting

[daveparslow]

Even though @internal is not officially defined in JSDoc, it is officially documented by TypeScript.

Documented on:
https://www.typescriptlang.org/docs/handbook/compiler-options.html

Example usage in TypeScript code base:
https://github.com/Microsoft/TypeScript/blob/v2.0.5/src/compiler/types.ts#L2297

TS and JS Grammar Extension version: 0.0.22 / latest

Code

/* @internal */
export interface Pattern {
        prefix: string;
        suffix: string;
}