Group content suggestions notifications separately

chrome/android/java/src/org/chromium/chrome/browser/ntp/ContentSuggestionsNotificationHelper.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/ContentSuggestionsNotificationHelper.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/ContentSuggestionsNotificationHelper.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/ContentSuggestionsNotificationHelper.java
index fb4056d042b5345374c7459d86ae96e70a890e1e..d17176a3dcfc5e4d544e4720aa7faf27213ac85d 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/ContentSuggestionsNotificationHelper.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/ContentSuggestionsNotificationHelper.java
@@ -62,6 +62,7 @@ public class ContentSuggestionsNotificationHelper {
                         .setContentIntent(PendingIntent.getActivity(context, 0, intent, 0))
                         .setContentTitle(title)
                         .setContentText(text)
+                        .setGroup(NOTIFICATION_TAG)
                         .setLargeIcon(image)
                         .setSmallIcon(R.drawable.ic_chrome);
         manager.notify(NOTIFICATION_TAG, NOTIFICATION_ID, builder.build());