NTP: track shown/blocked suggestions notifications

chrome/android/java/src/org/chromium/chrome/browser/notifications/NotificationUmaTracker.java

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.notifications;
 
 import android.content.SharedPreferences;
 import android.support.annotation.IntDef;
 import android.support.v4.app.NotificationManagerCompat;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.base.library_loader.LibraryLoader;
 import org.chromium.base.metrics.RecordHistogram;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 
 /**
  * Helper class to make tracking notification UMA stats easier for various features.  Having a
  * single entry point here to make more complex tracking easier to add in the future.
  */
 public class NotificationUmaTracker {
     @Retention(RetentionPolicy.SOURCE)
-    @IntDef({DOWNLOAD_FILES, DOWNLOAD_PAGES, CLOSE_INCOGNITO, SYSTEM_NOTIFICATION_TYPE_BOUNDARY})
+    @IntDef({DOWNLOAD_FILES, DOWNLOAD_PAGES, CLOSE_INCOGNITO, CONTENT_SUGGESTION,
+            SYSTEM_NOTIFICATION_TYPE_BOUNDARY})

[dgn, 2017/03/16 19:32:26]

Unrelated: IMO SYSTEM_NOTIFICATION_TYPE_BOUNDARY should not be in the enum, as
it's not really a valid value. But that has nothing to do with this CL and it's
private anyway ¯\_(ツ)_/¯

     public @interface SystemNotificationType {}
 
     /*
      * A list of notification types.  To add a type to this list please update
      * SystemNotificationType in histograms.xml and make sure to keep this list in sync.  Additions
      * should be treated as APPEND ONLY to keep the UMA metric semantics the same over time.
      *
      * A SystemNotificationType value can also be saved in shared preferences.
      */
     public static final int DOWNLOAD_FILES = 0;
     public static final int DOWNLOAD_PAGES = 1;
     public static final int CLOSE_INCOGNITO = 2;
+    public static final int CONTENT_SUGGESTION = 3;
 
-    private static final int SYSTEM_NOTIFICATION_TYPE_BOUNDARY = 3;
+    private static final int SYSTEM_NOTIFICATION_TYPE_BOUNDARY = 4;
 
     private static final String LAST_SHOWN_NOTIFICATION_TYPE_KEY =
             "NotificationUmaTracker.LastShownNotificationType";
 
     private static class LazyHolder {
         private static final NotificationUmaTracker INSTANCE = new NotificationUmaTracker();
     }
 
     /** Cached objects. */
     private final SharedPreferences mSharedPreferences;
@@ skipping 34 matching lines @@
         if (lastType == -1) return;
         mSharedPreferences.edit().remove(LAST_SHOWN_NOTIFICATION_TYPE_KEY).apply();
 
         recordHistogram("Mobile.SystemNotification.BlockedAfterShown", lastType);
     }
 
     private static void recordHistogram(String name, @SystemNotificationType int type) {
         if (!LibraryLoader.isInitialized()) return;
         RecordHistogram.recordEnumeratedHistogram(name, type, SYSTEM_NOTIFICATION_TYPE_BOUNDARY);
     }
-}
+}