[Media>UI] Don't show media metadata on lockscreen in Incognito mode

chrome/android/java/src/org/chromium/chrome/browser/media/ui/MediaNotificationManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/media/ui/MediaNotificationManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/media/ui/MediaNotificationManager.java b/chrome/android/java/src/org/chromium/chrome/browser/media/ui/MediaNotificationManager.java
index f13bd44ac299aaa35ba3914f4ddec5f6bc7e948e..080fbf78f108f191da5baf84a90b7414e444e816 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/media/ui/MediaNotificationManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/media/ui/MediaNotificationManager.java
@@ -673,7 +673,10 @@ public class MediaNotificationManager {
         clearNotification();
     }
 
+    @Nullable
     private MediaMetadataCompat createMetadata() {
+        if (mMediaNotificationInfo.isPrivate) return null;
+
         MediaMetadataCompat.Builder metadataBuilder = new MediaMetadataCompat.Builder();
 
         metadataBuilder.putString(MediaMetadataCompat.METADATA_KEY_TITLE,