Add Opt-in notification UMA for the Physical Web

chrome/android/java/src/org/chromium/chrome/browser/physicalweb/PhysicalWebOptInActivity.java

 // Copyright 2015 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.physicalweb;
 
 import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
 import android.support.v7.app.AppCompatActivity;
 import android.view.View;
 import android.widget.Button;
 
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.preferences.privacy.PrivacyPreferencesManager;
 
 /**
  * This activity invites the user to opt-in to the Physical Web feature.
  */
 public class PhysicalWebOptInActivity extends AppCompatActivity {
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.physical_web_optin);
+        PhysicalWebUma.onOptInNotificationPressed(this);
 
         Button declineButton = (Button) findViewById(R.id.physical_web_decline);
         declineButton.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
+                PhysicalWebUma.onOptInDeclineButtonPressed(PhysicalWebOptInActivity.this);
                 PrivacyPreferencesManager privacyPrefManager =
                         PrivacyPreferencesManager.getInstance(PhysicalWebOptInActivity.this);
                 privacyPrefManager.setPhysicalWebEnabled(false);
                 finish();
             }
         });
 
         Button enableButton = (Button) findViewById(R.id.physical_web_enable);
         enableButton.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
+                PhysicalWebUma.onOptInEnableButtonPressed(PhysicalWebOptInActivity.this);
                 PrivacyPreferencesManager privacyPrefManager =
                         PrivacyPreferencesManager.getInstance(PhysicalWebOptInActivity.this);
                 privacyPrefManager.setPhysicalWebEnabled(true);
                 startActivity(createListUrlsIntent(PhysicalWebOptInActivity.this));
                 finish();
             }
         });
     }
 
     private static Intent createListUrlsIntent(Context context) {
         Intent intent = new Intent(context, ListUrlsActivity.class);
         intent.putExtra(ListUrlsActivity.REFERER_KEY,
                 ListUrlsActivity.OPTIN_REFERER);
         return intent;
     }
-}
+}