Generics type for PerformanceMeasure and PerformanceMark

It would be really nice if I could create this type:

```ts
type myReturnValue = {
  mystuff: object,
  measurement: PerformanceMeasure<{ 
    /** best number */
    myNumber:number; 
    /** nice string */
    myString: string
  }>
}
```


related #1239
cc @yume-chan 