Windows: Factor out stat collector

Signed-off-by: John Howard <jhoward@microsoft.com>

daemon/stats_collector_unix.go

@@ -1,3 +1,5 @@
+// +build !windows
+
 package daemon
 
 import (

daemon/stats_collector_windows.go

@@ -0,0 +1,31 @@
+package daemon
+
+import "time"
+
+// newStatsCollector returns a new statsCollector for collection stats
+// for a registered container at the specified interval. The collector allows
+// non-running containers to be added and will start processing stats when
+// they are started.
+func newStatsCollector(interval time.Duration) *statsCollector {
+	return &statsCollector{}
+}
+
+// statsCollector manages and provides container resource stats
+type statsCollector struct {
+}
+
+// collect registers the container with the collector and adds it to
+// the event loop for collection on the specified interval returning
+// a channel for the subscriber to receive on.
+func (s *statsCollector) collect(c *Container) chan interface{} {
+	return nil
+}
+
+// stopCollection closes the channels for all subscribers and removes
+// the container from metrics collection.
+func (s *statsCollector) stopCollection(c *Container) {
+}
+
+// unsubscribe removes a specific subscriber from receiving updates for a container's stats.
+func (s *statsCollector) unsubscribe(c *Container, ch chan interface{}) {
+}