diff -r 000000000000 -r 6474c204b198 browser/metro/base/content/startui/StartUI.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/metro/base/content/startui/StartUI.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,153 @@
+/* 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";
+
+Cu.import("resource://gre/modules/Services.jsm");
+
+var StartUI = {
+  get startUI() { return document.getElementById("start-container"); },
+
+  get chromeWin() {
+    // XXX Not e10s friendly. We use this in a few places.
+    return Services.wm.getMostRecentWindow('navigator:browser');
+  },
+
+  init: function init() {
+    this.startUI.addEventListener("click", this, false);
+    this.startUI.addEventListener("MozMousePixelScroll", this, false);
+
+    // Update the input type on our local broadcaster
+    document.getElementById("bcast_preciseInput").setAttribute("input",
+      this.chromeWin.InputSourceHelper.isPrecise ? "precise" : "imprecise");
+
+    let firstRunCount = Services.prefs.getIntPref("browser.firstrun.count");
+    if (firstRunCount > 0) {
+      document.loadOverlay("chrome://browser/content/FirstRunOverlay.xul", null);
+      Services.prefs.setIntPref("browser.firstrun.count", firstRunCount - 1);
+    }
+
+    this._adjustDOMforViewState(this.chromeWin.ContentAreaObserver.viewstate);
+
+    TopSitesStartView.init();
+    BookmarksStartView.init();
+    HistoryStartView.init();
+    RemoteTabsStartView.init();
+
+    this.chromeWin.addEventListener("MozPrecisePointer", this, true);
+    this.chromeWin.addEventListener("MozImprecisePointer", this, true);
+    this.chromeWin.addEventListener("MozAfterPaint", this, true);
+    this.chromeWin.Elements.panelUI.addEventListener("ToolPanelHidden", this, false);
+
+    Services.obs.addObserver(this, "metro_viewstate_changed", false);
+  },
+
+  uninit: function() {
+    if (TopSitesStartView)
+      TopSitesStartView.uninit();
+    if (BookmarksStartView)
+      BookmarksStartView.uninit();
+    if (HistoryStartView)
+      HistoryStartView.uninit();
+    if (RemoteTabsStartView)
+      RemoteTabsStartView.uninit();
+
+    if (this.chromeWin) {
+      this.chromeWin.removeEventListener("MozPrecisePointer", this, true);
+      this.chromeWin.removeEventListener("MozImprecisePointer", this, true);
+    }
+    Services.obs.removeObserver(this, "metro_viewstate_changed");
+  },
+
+  goToURI: function (aURI) {
+    this.chromeWin.BrowserUI.goToURI(aURI);
+  },
+
+  onClick: function onClick(aEvent) {
+    // If someone clicks / taps in empty grid space, take away
+    // focus from the nav bar edit so the soft keyboard will hide.
+    this.chromeWin.BrowserUI.blurNavBar();
+
+    if (aEvent.button == 0) {
+      this.chromeWin.ContextUI.dismissTabs();
+    }
+  },
+
+  onNarrowTitleClick: function onNarrowTitleClick(sectionId) {
+    let section = document.getElementById(sectionId);
+
+    if (section.hasAttribute("expanded"))
+      return;
+
+    for (let expandedSection of this.startUI.querySelectorAll(".meta-section[expanded]"))
+      expandedSection.removeAttribute("expanded")
+
+    section.setAttribute("expanded", "true");
+  },
+
+  _adjustDOMforViewState: function(aState) {
+    document.getElementById("bcast_windowState").setAttribute("viewstate", aState);
+  },
+
+  handleEvent: function handleEvent(aEvent) {
+    switch (aEvent.type) {
+      case "MozPrecisePointer":
+        document.getElementById("bcast_preciseInput").setAttribute("input", "precise");
+        break;
+      case "MozImprecisePointer":
+        document.getElementById("bcast_preciseInput").setAttribute("input", "imprecise");
+        break;
+      case "click":
+        this.onClick(aEvent);
+        break;
+      case "MozMousePixelScroll":
+        let viewstate = this.startUI.getAttribute("viewstate");
+        if (viewstate === "snapped" || viewstate === "portrait") {
+          window.scrollBy(0, aEvent.detail);
+        } else {
+          window.scrollBy(aEvent.detail, 0);
+        }
+
+        aEvent.preventDefault();
+        aEvent.stopPropagation();
+        break;
+      case "ToolPanelHidden":
+        // After opening panel UI (console) set disableZoom again.
+        this.chromeWin.addEventListener("MozAfterPaint", this, true);
+        break;
+
+      case "MozAfterPaint":
+        this._disableZoom();
+        this.chromeWin.removeEventListener("MozAfterPaint", this, true);
+        break;
+    }
+  },
+
+  observe: function (aSubject, aTopic, aData) {
+    switch (aTopic) {
+      case "metro_viewstate_changed":
+        this._adjustDOMforViewState(aData);
+        break;
+    }
+  },
+
+  _disableZoom: function() {
+    let utils = Util.getWindowUtils(window);
+    let viewId;
+    try {
+      viewId = utils.getViewId(document.documentElement);
+    } catch(e) {
+      return;
+    }
+
+    let presShellId = {};
+    utils.getPresShellId(presShellId);
+
+    let notificationData = [
+      presShellId.value,
+      viewId].join(",");
+
+    Services.obs.notifyObservers(null, "apzc-disable-zoom", notificationData);
+  }
+};