Revert "Messaging: Add "Mark as read" quick action for message notifications"

This reverts commit f19e916a0d.

Reason for revert: Reverting per Taesu Lee's comments, because it doesn't work and has issues.

Change-Id: I778362b628f4c3ae076dd943e77dee415984fba0

src/com/android/messaging/ui/UIIntentsImpl.java

@@ -431,20 +431,6 @@ public class UIIntentsImpl extends UIIntents {
                 PendingIntent.FLAG_UPDATE_CURRENT);
     }
 
-    @Override
-    public PendingIntent getPendingIntentForMarkingAsRead(final Context context,
-            final ConversationIdSet conversationIdSet, final int requestCode) {
-        final Intent intent = new Intent(context, NotificationReceiver.class);
-        intent.setAction(ACTION_MARK_AS_READ);
-        if (conversationIdSet != null) {
-            intent.putExtra(UI_INTENT_EXTRA_CONVERSATION_ID_SET,
-                    conversationIdSet.getDelimitedString());
-        }
-        return PendingIntent.getBroadcast(context,
-                requestCode, intent,
-                PendingIntent.FLAG_UPDATE_CURRENT);
-    }
-
     /**
      * Gets a PendingIntent associated with an Intent to start an Activity. All notifications
      * that starts an Activity must use this method to get a PendingIntent, which achieves two