IPH - Added triggers for Download page

components/feature_engagement_tracker/public/BUILD.gn

 # 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.
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
 
 source_set("public") {
   sources = [
     "feature_constants.h",
     "feature_engagement_tracker.h",
   ]
 
   deps = [
     "//base",
     "//components/keyed_service/core",
   ]
 
   if (is_android) {
     sources += [ "android/feature_engagement_tracker_jni_registrar.h" ]
   }
 }
 
 if (is_android) {
   android_library("public_java") {
     java_files = [
+      "android/java/src/org/chromium/components/feature_engagement_tracker/EventConstants.java",
       "android/java/src/org/chromium/components/feature_engagement_tracker/FeatureConstants.java",
       "android/java/src/org/chromium/components/feature_engagement_tracker/FeatureEngagementTracker.java",
     ]
 
     deps = [
       "//base:base_java",
       "//third_party/android_tools:android_support_annotations_java",
     ]
   }
 }