Revamp the Incognito NTP on Desktop

chrome/browser/resources/ntp4/md_incognito_tab.js

+// Copyright 2017 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";
+
+// Handle the bookmark bar and theme change requests from the C++ side.
+cr.define('ntp', function() {
+  /**
+   * Set whether the bookmarks bar is attached or not.
+   * @param {boolean} attached Whether the bar is attached or not.
+   */
+  function setBookmarkBarAttached(attached) {
+    document.documentElement.setAttribute('bookmarkbarattached', !!attached);
+  }
+
+  /** @param {!{hasCustomBackground: boolean}} themeData */
+  function themeChanged(themeData) {
+    document.documentElement.setAttribute('hascustombackground',
+                                          themeData.hasCustomBackground);
+    $('incognitothemecss').href =
+        'chrome://theme/css/incognito_new_tab_theme.css?' + Date.now();
+  }
+
+  return {
+    setBookmarkBarAttached: setBookmarkBarAttached,
+    themeChanged: themeChanged,
+  };
+});
+
+// Let the width of two lists of bulletpoints in a horizontal alignment
+// determine the maximum content width.
+window.addEventListener('load', function() {
+  var b1 = $('firstBulletpoints');
+  var b2 = $('secondBulletpoints');
+  var c = document.querySelector('.content');
+
+  var maxWidth = (b1.offsetWidth + b2.offsetWidth +
+      40 /* margin */ + 2 /* offsetWidths may be rounded down */);
+
+  // Limit the maximum width to 600px. That might force the two lists
+  // of bulletpoints under each other, in which case we must swap the left
+  // and right margin.
+  if (maxWidth > 600) {
+    maxWidth = 600;
+
+    b2.className += " tooWide";
+  }
+
+  c.style.maxWidth = maxWidth + "px";
+});