}

// Sync notifies the generator of an EventSync event.
func (g *procRangeGenerator) Sync() {
	g.seenSync = true
}

// ProcRange implements a handler for EventRange* events whose Scope.Kind is ResourceProc.
// It expects ev to be one such event.
func (g *procRangeGenerator) ProcRange(ctx *traceContext, ev *trace.Event) {
	if g.ranges == nil {
		g.ranges = make(map[trace.Range]activeRange)
	}
	r := ev.Range()

	_, inMarkAssist := gs.activeRanges["GC mark assist"]
	ctx.GoroutineTransition(ctx.elapsed(ev.Time()), viewerGState(from, inMarkAssist), viewerGState(to, inMarkAssist))
}

func (g *goroutineGenerator) ProcRange(ctx *traceContext, ev *trace.Event) {
	// TODO(mknyszek): Extend procRangeGenerator to support rendering proc ranges
	// that overlap with a goroutine's execution.
}

	// events for this to clearly delineate GOMAXPROCS changes.

	if viewerEv.Name != "" {
		ctx.Instant(viewerEv)
	}
}

func (g *threadGenerator) ProcRange(ctx *traceContext, ev *trace.Event) {
	// TODO(mknyszek): Extend procRangeGenerator to support rendering proc ranges on threads.
}

func (g *threadGenerator) Finish(ctx *traceContext) {