Rename watch.Mux -> watch.Broadcaster

A few reasons:
- Mux is already widely used in the codebase to refer to a http handler mux.
- Original meaning of Mux was something which sent a chose one of several inputs to
  and output.  This sends one output to all outputs.  Broadcast captures that idea
  better.
- Aligns with similar class config.Broadcaster (see #2747)

pkg/registry/registrytest/generic.go

@@ -33,13 +33,13 @@ type GenericRegistry struct {
 	ObjectList runtime.Object
 	sync.Mutex
 
-	Mux *watch.Mux
+	Broadcaster *watch.Broadcaster
 }
 
 func NewGeneric(list runtime.Object) *GenericRegistry {
 	return &GenericRegistry{
-		ObjectList: list,
-		Mux:        watch.NewMux(0),
+		ObjectList:  list,
+		Broadcaster: watch.NewBroadcaster(0),
 	}
 }
 
@@ -54,7 +54,7 @@ func (r *GenericRegistry) List(ctx api.Context, m generic.Matcher) (runtime.Obje
 
 func (r *GenericRegistry) Watch(ctx api.Context, m generic.Matcher, resourceVersion string) (watch.Interface, error) {
 	// TODO: wire filter down into the mux; it needs access to current and previous state :(
-	return r.Mux.Watch(), nil
+	return r.Broadcaster.Watch(), nil
 }
 
 func (r *GenericRegistry) Get(ctx api.Context, id string) (runtime.Object, error) {
@@ -67,7 +67,7 @@ func (r *GenericRegistry) Create(ctx api.Context, id string, obj runtime.Object)
 	r.Lock()
 	defer r.Unlock()
 	r.Object = obj
-	r.Mux.Action(watch.Added, obj)
+	r.Broadcaster.Action(watch.Added, obj)
 	return r.Err
 }
 
@@ -75,13 +75,13 @@ func (r *GenericRegistry) Update(ctx api.Context, id string, obj runtime.Object)
 	r.Lock()
 	defer r.Unlock()
 	r.Object = obj
-	r.Mux.Action(watch.Modified, obj)
+	r.Broadcaster.Action(watch.Modified, obj)
 	return r.Err
 }
 
 func (r *GenericRegistry) Delete(ctx api.Context, id string) error {
 	r.Lock()
 	defer r.Unlock()
-	r.Mux.Action(watch.Deleted, r.Object)
+	r.Broadcaster.Action(watch.Deleted, r.Object)
 	return r.Err
 }

pkg/registry/registrytest/pod.go

@@ -30,13 +30,13 @@ type PodRegistry struct {
 	Pods *api.PodList
 	sync.Mutex
 
-	mux *watch.Mux
+	broadcaster *watch.Broadcaster
 }
 
 func NewPodRegistry(pods *api.PodList) *PodRegistry {
 	return &PodRegistry{
-		Pods: pods,
-		mux:  watch.NewMux(0),
+		Pods:        pods,
+		broadcaster: watch.NewBroadcaster(0),
 	}
 }
 
@@ -64,8 +64,8 @@ func (r *PodRegistry) ListPods(ctx api.Context, selector labels.Selector) (*api.
 }
 
 func (r *PodRegistry) WatchPods(ctx api.Context, resourceVersion string, filter func(*api.Pod) bool) (watch.Interface, error) {
-	// TODO: wire filter down into the mux; it needs access to current and previous state :(
-	return r.mux.Watch(), nil
+	// TODO: wire filter down into the broadcaster; it needs access to current and previous state :(
+	return r.broadcaster.Watch(), nil
 }
 
 func (r *PodRegistry) GetPod(ctx api.Context, podId string) (*api.Pod, error) {
@@ -78,7 +78,7 @@ func (r *PodRegistry) CreatePod(ctx api.Context, pod *api.Pod) error {
 	r.Lock()
 	defer r.Unlock()
 	r.Pod = pod
-	r.mux.Action(watch.Added, pod)
+	r.broadcaster.Action(watch.Added, pod)
 	return r.Err
 }
 
@@ -86,13 +86,13 @@ func (r *PodRegistry) UpdatePod(ctx api.Context, pod *api.Pod) error {
 	r.Lock()
 	defer r.Unlock()
 	r.Pod = pod
-	r.mux.Action(watch.Modified, pod)
+	r.broadcaster.Action(watch.Modified, pod)
 	return r.Err
 }
 
 func (r *PodRegistry) DeletePod(ctx api.Context, podId string) error {
 	r.Lock()
 	defer r.Unlock()
-	r.mux.Action(watch.Deleted, r.Pod)
+	r.broadcaster.Action(watch.Deleted, r.Pod)
 	return r.Err
 }