resume method
Resumes after a pause.
This undoes one previous call to pause.
When all previously calls to pause have been matched by a calls to
resume, possibly through a resumeSignal
passed to pause,
the stream subscription may emit events again.
It is safe to resume even when the subscription is not paused, and the resume will have no effect.
Implementation
@override
void resume() {
_source.resume();
}