First attempt at creating a first-run page

firstRun.js

+var backgroundPage = chrome.extension.getBackgroundPage();
+var require = backgroundPage.require;
+var Prefs = require("prefs").Prefs;
+var Utils = require("utils").Utils;
+
+function init()
+{
+  // Choose a share text variant randomly
+  var variant = Math.floor(Math.random() * 2) + 1;
+  document.documentElement.setAttribute("share-variant", variant);
+
+  // Set up page title
+  var titleId = (backgroundPage.isFirstRun ? "firstRun_title_install" : "firstRun_title_update");
+  var pageTitle = chrome.i18n.getMessage(titleId);
+  document.title = document.getElementById("title").textContent = pageTitle;
+
+  // Set up URLs
+  var versionID = chrome.app.getDetails().version.split(".").slice(0, 2).join("");
+  setLinks("improvementsFeature", "https://adblockplus.org/releases/adblock-plus-" + versionID + "-for-google-chrome-released");
+  setLinks("acceptableAdsExplanation", getDocLink("acceptable_ads"),
+           getDocLink("acceptable_ads", "criteria"), backgroundPage.openOptions);
+
+  var facebookLinks = document.getElementsByClassName("share-facebook");
+  for (var i = 0; i < facebookLinks.length; i++)
+    facebookLinks[i].href = getDocLink("facebook") + "&variant=" + variant;
+
+  var twitterLinks = document.getElementsByClassName("share-twitter");
+  for (var i = 0; i < twitterLinks.length; i++)
+    twitterLinks[i].href = getDocLink("twitter") + "&variant=" + variant;
+
+  var donateLink = document.getElementById("share-donate");
+  donateLink.href = getDocLink("donate") + "&variant=" + variant;
+}
+window.addEventListener("load", init, false);
+
+function setLinks(id)
+{
+  var element = document.getElementById(id);
+  if (!element)
+    return;
+
+  var links = element.getElementsByTagName("a");
+  for (var i = 0; i < links.length; i++)
+  {
+    if (typeof arguments[i + 1] == "string")
+    {
+      links[i].href = arguments[i + 1];
+      links[i].setAttribute("target", "_blank");
+    }
+    else if (typeof arguments[i + 1] == "function")
+    {
+      links[i].href = "javascript:void(0);";
+      links[i].addEventListener("click", arguments[i + 1], false);
+    }
+  }
+}
+
+function getDocLink(page, anchor)
+{
+  return Prefs.documentation_link
+              .replace(/%LINK%/g, page)
+              .replace(/%LANG%/g, Utils.appLocale) + (anchor ? "#" + anchor : "");
+}