Use experimentation framework parameters for location sensitivity

chrome/browser/resources/google_now/background.js

 // Copyright (c) 2013 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.
 
 'use strict';
 
 /**
  * @fileoverview The event page for Google Now for Chrome implementation.
  * The Google Now event page gets Google Now cards from the server and shows
  * them as Chrome notifications.
@@ skipping 100 matching lines @@
     return true;
   }
 
   return false;
 }
 
 var tasks = buildTaskManager(areTasksConflicting);
 
 // Add error processing to API calls.
 tasks.instrumentChromeApiFunction('location.onLocationUpdate.addListener', 0);
+tasks.instrumentChromeApiFunction('metricsPrivate.getVariationParams', 1);
 tasks.instrumentChromeApiFunction('notifications.create', 2);
 tasks.instrumentChromeApiFunction('notifications.update', 2);
 tasks.instrumentChromeApiFunction('notifications.getAll', 0);
 tasks.instrumentChromeApiFunction(
     'notifications.onButtonClicked.addListener', 0);
 tasks.instrumentChromeApiFunction('notifications.onClicked.addListener', 0);
 tasks.instrumentChromeApiFunction('notifications.onClosed.addListener', 0);
 tasks.instrumentChromeApiFunction('omnibox.onInputEntered.addListener', 0);
 tasks.instrumentChromeApiFunction(
     'preferencesPrivate.googleGeolocationAccessEnabled.get',
@@ skipping 262 matching lines @@
     }
   });
 }
 
 /**
  * Starts getting location for a cards update.
  */
 function requestLocation() {
   console.log('requestLocation');
   recordEvent(GoogleNowEvent.LOCATION_REQUEST);
-  // TODO(vadimt): Figure out location request options. Use experiments
-  // framework to enable setting these parameters remotely.
-  chrome.location.watchLocation(LOCATION_WATCH_NAME, {
-    minDistanceInMeters: 100,
-    minTimeInMilliseconds: 180000  // 3 minutes.
+  // TODO(vadimt): Figure out location request options.
+  chrome.metricsPrivate.getVariationParams('GoogleNow', function(params) {
+    var minDistanceInMeters =
+        parseInt(params && params.minDistanceInMeters, 10) ||
+        100;
+    var minTimeInMilliseconds =
+        parseInt(params && params.minTimeInMilliseconds, 10) ||
+        180000;  // 3 minutes.
+
+    chrome.location.watchLocation(LOCATION_WATCH_NAME, {
+      minDistanceInMeters: minDistanceInMeters,
+      minTimeInMilliseconds: minTimeInMilliseconds
+    });
   });
 }
 
 /**
  * Stops getting the location.
  */
 function stopRequestLocation() {
   console.log('stopRequestLocation');
   chrome.location.clearWatch(LOCATION_WATCH_NAME);
 }
@@ skipping 507 matching lines @@
 
 instrumented.location.onLocationUpdate.addListener(function(position) {
   recordEvent(GoogleNowEvent.LOCATION_UPDATE);
   updateNotificationsCards(position);
 });
 
 instrumented.omnibox.onInputEntered.addListener(function(text) {
   localStorage['server_url'] = NOTIFICATION_CARDS_URL = text;
   initialize();
 });