Added video time tracking.

I just remembered something else: in a fully compliant promises/A implementation it's very likely that all the times will be off due to what I mentioned above.

- Method is called (let's say this is time A) and the value of undefined in returned.
- The variable is set as time A
- Method is called again (time B this time) and the value of B is returned.
- The promise is executed again and the variable is set as time B.
- And so on...