diff -r 000000000000 -r 6474c204b198 browser/components/translation/Translation.jsm
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/translation/Translation.jsm	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,140 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+this.EXPORTED_SYMBOLS = ["Translation"];
+
+const {classes: Cc, interfaces: Ci, utils: Cu} = Components;
+
+Cu.import("resource://gre/modules/Promise.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+this.Translation = {
+  supportedSourceLanguages: ["en", "zh", "ja", "es", "de", "fr", "ru", "ar", "ko", "pt"],
+  supportedTargetLanguages: ["en", "pl", "tr", "vi"],
+
+  _defaultTargetLanguage: "",
+  get defaultTargetLanguage() {
+    if (!this._defaultTargetLanguage) {
+      this._defaultTargetLanguage = Cc["@mozilla.org/chrome/chrome-registry;1"]
+                                      .getService(Ci.nsIXULChromeRegistry)
+                                      .getSelectedLocale("global")
+                                      .split("-")[0];
+    }
+    return this._defaultTargetLanguage;
+  },
+
+  languageDetected: function(aBrowser, aDetectedLanguage) {
+    if (this.supportedSourceLanguages.indexOf(aDetectedLanguage) != -1 &&
+        aDetectedLanguage != this.defaultTargetLanguage) {
+      if (!aBrowser.translationUI)
+        aBrowser.translationUI = new TranslationUI(aBrowser);
+
+      aBrowser.translationUI.showTranslationUI(aDetectedLanguage);
+    }
+  }
+};
+
+/* TranslationUI objects keep the information related to translation for
+ * a specific browser.  This object is passed to the translation
+ * infobar so that it can initialize itself.  The properties exposed to
+ * the infobar are:
+ * - detectedLanguage, code of the language detected on the web page.
+ * - state, the state in which the infobar should be displayed
+ * - STATE_{OFFER,TRANSLATING,TRANSLATED,ERROR} constants.
+ * - translatedFrom, if already translated, source language code.
+ * - translatedTo, if already translated, target language code.
+ * - translate, method starting the translation of the current page.
+ * - showOriginalContent, method showing the original page content.
+ * - showTranslatedContent, method showing the translation for an
+ *   already translated page whose original content is shown.
+ * - originalShown, boolean indicating if the original or translated
+ *   version of the page is shown.
+ */
+function TranslationUI(aBrowser) {
+  this.browser = aBrowser;
+}
+
+TranslationUI.prototype = {
+  STATE_OFFER: 0,
+  STATE_TRANSLATING: 1,
+  STATE_TRANSLATED: 2,
+  STATE_ERROR: 3,
+
+  get doc() this.browser.contentDocument,
+
+  translate: function(aFrom, aTo) {
+    this.state = this.STATE_TRANSLATING;
+    this.translatedFrom = aFrom;
+    this.translatedTo = aTo;
+  },
+
+  showURLBarIcon: function(aTranslated) {
+    let chromeWin = this.browser.ownerGlobal;
+    let PopupNotifications = chromeWin.PopupNotifications;
+    let removeId = aTranslated ? "translate" : "translated";
+    let notification =
+      PopupNotifications.getNotification(removeId, this.browser);
+    if (notification)
+      PopupNotifications.remove(notification);
+
+    let callback = aTopic => {
+      if (aTopic != "showing")
+        return false;
+      if (!this.notificationBox.getNotificationWithValue("translation"))
+        this.showTranslationInfoBar();
+      return true;
+    };
+
+    let addId = aTranslated ? "translated" : "translate";
+    PopupNotifications.show(this.browser, addId, null,
+                            addId + "-notification-icon", null, null,
+                            {dismissed: true, eventCallback: callback});
+  },
+
+  _state: 0,
+  get state() this._state,
+  set state(val) {
+    let notif = this.notificationBox.getNotificationWithValue("translation");
+    if (notif)
+      notif.state = val;
+    this._state = val;
+  },
+
+  originalShown: true,
+  showOriginalContent: function() {
+    this.showURLBarIcon();
+    this.originalShown = true;
+  },
+
+  showTranslatedContent: function() {
+    this.showURLBarIcon(true);
+    this.originalShown = false;
+  },
+
+  get notificationBox() this.browser.ownerGlobal.gBrowser.getNotificationBox(),
+
+  showTranslationInfoBar: function() {
+    let notificationBox = this.notificationBox;
+    let notif = notificationBox.appendNotification("", "translation", null,
+                                                   notificationBox.PRIORITY_INFO_HIGH);
+    notif.init(this);
+    return notif;
+  },
+
+  showTranslationUI: function(aDetectedLanguage) {
+    this.detectedLanguage = aDetectedLanguage;
+
+    // Reset all values before showing a new translation infobar.
+    this.state = 0;
+    this.translatedFrom = "";
+    this.translatedTo = "";
+    this.originalShown = true;
+
+    this.showURLBarIcon();
+    return this.showTranslationInfoBar();
+  }
+};