[Android,MediaFling] Create and register the notification object early

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

Index: chrome/android/java/src/org/chromium/chrome/browser/media/remote/CastNotificationControl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/media/remote/CastNotificationControl.java b/chrome/android/java/src/org/chromium/chrome/browser/media/remote/CastNotificationControl.java
index 2dfc2dff9ade336ba265fd8543aa424140260cc7..5e09e0935e578ca7998430b66f2d811326d922db 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/media/remote/CastNotificationControl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/media/remote/CastNotificationControl.java
@@ -60,7 +60,7 @@ public class CastNotificationControl implements MediaRouteController.UiListener,
             if (sInstance == null) {
                 sInstance = new CastNotificationControl(context);
             }
-            sInstance.mMediaRouteController = mediaRouteController;
+            sInstance.setRouteController(mediaRouteController);
             return sInstance;
         }
     }
@@ -117,10 +117,15 @@ public class CastNotificationControl implements MediaRouteController.UiListener,
     }
 
     public void setRouteController(MediaRouteController controller) {
+        if (mMediaRouteController != null) mMediaRouteController.removeUiListener(this);
         mMediaRouteController = controller;
+        if (controller != null) controller.addUiListener(this);
     }
 
     private void updateNotification() {
+        // Nothing shown yet, nothing to update.
+        if (mNotificationBuilder == null) return;
+
         mNotificationBuilder.setMetadata(new MediaMetadata(mTitle, "", ""));
         if (mState == PlayerState.PAUSED || mState == PlayerState.PLAYING) {
             mNotificationBuilder.setPaused(mState != PlayerState.PLAYING);
@@ -146,6 +151,8 @@ public class CastNotificationControl implements MediaRouteController.UiListener,
     // MediaRouteController.UiListener implementation.
     @Override
     public void onPlaybackStateChanged(PlayerState newState) {
+        if (mState == newState) return;
+
         mState = newState;
         updateNotification();
     }
@@ -177,7 +184,9 @@ public class CastNotificationControl implements MediaRouteController.UiListener,
 
     @Override
     public void onTitleChanged(String title) {
-        mTitle = (title == null) ? "" : title;
+        if (title == null || title.equals(mTitle)) return;
+
+        mTitle = title;
         updateNotification();
     }