Added survey butter-bar to web-app.

remoting/webapp/survey.js

+// Copyright 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.
+
+/**
+ * @fileoverview
+ * Functions and event handlers to invite the user to participate in a survey
+ * to help improve the product.
+ */
+
+'use strict';
+
+/** @suppress {duplicate} */
+var remoting = remoting || {};
+
+var kStorageKey = 'feedback-survey-dismissed';
+var kSurveyDivId = 'survey-opt-in';
+var kSurveyAcceptId = 'survey-accept';
+var kSurveyDeclineId = 'survey-decline';
+
+/**
+ * Hide the survey request and record some basic information about the current
+ * state of the world in synced storage. This may be useful in the future if we
+ * want to show the request again. At the moment, the data itself is ignored;
+ * only its presence or absence is important.
+ *
+ * @param {boolean} optIn True if the user clicked the "Take the survey" link;
+ *     false if they clicked the close icon.
+ */
+remoting.dismissSurvey = function(optIn) {
+  var value = {};
+  value[kStorageKey] = {
+    optIn: optIn,
+    date: new Date(),
+    version: chrome.runtime.getManifest().version
+  };

[Jamie, 2013/03/20 00:32:52]

Is there anything else you'd like to see saved here that we might want to use
later on to decide whether or not to re-show the butter-bar to a subset of
users?

+  chrome.storage.sync.set(value);
+  document.getElementById(kSurveyDivId).hidden = true;
+};
+
+/**
+ * Show or hide the survey request, depending on whether or not the user has
+ * already seen it.
+ */
+remoting.initSurvey = function() {
+  /** @param {Object} value */
+  var onFeedbackSurveyInfo = function(value) {
+    /** @type {*} */
+    var dismissed = value[kStorageKey];
+    document.getElementById(kSurveyDivId).hidden = !!dismissed;
+  };
+  chrome.storage.sync.get(kStorageKey, onFeedbackSurveyInfo);
+  var accept = document.getElementById(kSurveyAcceptId);
+  var decline = document.getElementById(kSurveyDeclineId);
+  accept.addEventListener(
+      'click', remoting.dismissSurvey.bind(null, true), false);
+  decline.addEventListener(
+      'click', remoting.dismissSurvey.bind(null, false), false);
+};