[Android, Cast] Take onRouteChanged() into account to discover compatible Cast devices.

chrome/android/java/src/org/chromium/chrome/browser/media/remote/AbstractMediaRouteController.java

Index: chrome/android/java/src/org/chromium/chrome/browser/media/remote/AbstractMediaRouteController.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/media/remote/AbstractMediaRouteController.java b/chrome/android/java/src/org/chromium/chrome/browser/media/remote/AbstractMediaRouteController.java
index 19d758a21298762d48498458aa1611937f1d2673..c6e08b123d67cd3a736e432c79d4d22a602c3b18 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/media/remote/AbstractMediaRouteController.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/media/remote/AbstractMediaRouteController.java
@@ -73,6 +73,14 @@ public abstract class AbstractMediaRouteController implements MediaRouteControll
             updateRouteAvailability();
         }
 
+        @Override
+        public void onRouteChanged(MediaRouter router, RouteInfo route) {
+            if (mDebug) {
+                Log.d(TAG, "Changed route " + route.getName() + " " + route.getId());
+            }
+            updateRouteAvailability();
+        }
+
         private void updateRouteAvailability() {
             if (mediaRouterInitializationFailed()) return;