Update Ash network icon code and integrate with tray

ash/system/chromeos/network/network_icon_animation.cc

Index: ash/system/chromeos/network/network_icon_animation.cc
diff --git a/ash/system/chromeos/network/network_icon_animation.cc b/ash/system/chromeos/network/network_icon_animation.cc
index 55cc7f03c53346da50abedc5f7bac354dbb781cc..55da41e64df01d43dc4a3121f21aa00a559dabf9 100644
--- a/ash/system/chromeos/network/network_icon_animation.cc
+++ b/ash/system/chromeos/network/network_icon_animation.cc
@@ -48,6 +48,17 @@ void NetworkIconAnimation::RemoveObserver(AnimationObserver* observer) {
     animation_.Stop();
 }
 
+void NetworkIconAnimation::AddNetwork(const std::string& network_id) {
+  networks_.insert(network_id);
+  // Animation will start (if stopped) when GetAnimation is called.
+}
+
+void NetworkIconAnimation::RemoveNetwork(const std::string& network_id) {
+  networks_.erase(network_id);
+  if (networks_.empty())
+    animation_.Reset();
+}
+
 // static
 NetworkIconAnimation* NetworkIconAnimation::GetInstance() {
   static NetworkIconAnimation* s_icon_animation =