Run tools/clang-format-js on some of chrome/browser/resources/

chrome/browser/resources/local_ntp/most_visited_single.js

Index: chrome/browser/resources/local_ntp/most_visited_single.js
diff --git a/chrome/browser/resources/local_ntp/most_visited_single.js b/chrome/browser/resources/local_ntp/most_visited_single.js
index aba6f846b8be4c88f90cd88fb7985937fe93cd42..8298871290c383a5af6e568fa367d9cd286d7bb9 100644
--- a/chrome/browser/resources/local_ntp/most_visited_single.js
+++ b/chrome/browser/resources/local_ntp/most_visited_single.js
@@ -2,597 +2,612 @@
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file. */
 
- // Single iframe for NTP tiles.
+// Single iframe for NTP tiles.
 (function() {
-'use strict';
-
-
-/**
- * The different types of events that are logged from the NTP.  This enum is
- * used to transfer information from the NTP JavaScript to the renderer and is
- * not used as a UMA enum histogram's logged value.
- * Note: Keep in sync with common/ntp_logging_events.h
- * @enum {number}
- * @const
- */
-var LOG_TYPE = {
-  // All NTP Tiles have finished loading (successfully or failing).
-  NTP_ALL_TILES_LOADED: 11,
-};
-
-
-/**
- * The different sources that an NTP tile can have.
- * Note: Keep in sync with components/ntp_tiles/ntp_tile_source.h
- * @enum {number}
- * @const
- */
-var NTPTileSource = {
-  TOP_SITES: 0,
-  SUGGESTIONS_SERVICE: 1,
-  POPULAR: 3,
-  WHITELIST: 4,
-};
-
-
-/**
- * Total number of tiles to show at any time. If the host page doesn't send
- * enough tiles, we fill them blank.
- * @const {number}
- */
-var NUMBER_OF_TILES = 8;
-
-
-/**
- * Whether to use icons instead of thumbnails.
- * @type {boolean}
- */
-var USE_ICONS = false;
-
-
-/**
- * Number of lines to display in titles.
- * @type {number}
- */
-var NUM_TITLE_LINES = 1;
-
-
-/**
- * The origin of this request.
- * @const {string}
- */
-var DOMAIN_ORIGIN = '{{ORIGIN}}';
-
-
-/**
- * Counter for DOM elements that we are waiting to finish loading.
- * @type {number}
- */
-var loadedCounter = 1;
-
-
-/**
- * DOM element containing the tiles we are going to present next.
- * Works as a double-buffer that is shown when we receive a "show" postMessage.
- * @type {Element}
- */
-var tiles = null;
-
-
-/**
- * List of parameters passed by query args.
- * @type {Object}
- */
-var queryArgs = {};
-
-
-/**
- * Log an event on the NTP.
- * @param {number} eventType Event from LOG_TYPE.
- */
-var logEvent = function(eventType) {
-  chrome.embeddedSearch.newTabPage.logEvent(eventType);
-};
-
-/**
- * Log impression of an NTP tile.
- * @param {number} tileIndex Position of the tile, >= 0 and < NUMBER_OF_TILES.
- * @param {number} tileSource The source from NTPTileSource.
- */
-function logMostVisitedImpression(tileIndex, tileSource) {
-  chrome.embeddedSearch.newTabPage.logMostVisitedImpression(tileIndex,
-                                                            tileSource);
-}
-
-/**
- * Log click on an NTP tile.
- * @param {number} tileIndex Position of the tile, >= 0 and < NUMBER_OF_TILES.
- * @param {number} tileSource The source from NTPTileSource.
- */
-function logMostVisitedNavigation(tileIndex, tileSource) {
-  chrome.embeddedSearch.newTabPage.logMostVisitedNavigation(tileIndex,
-                                                            tileSource);
-}
-
-/**
- * Down counts the DOM elements that we are waiting for the page to load.
- * When we get to 0, we send a message to the parent window.
- * This is usually used as an EventListener of onload/onerror.
- */
-var countLoad = function() {
-  loadedCounter -= 1;
-  if (loadedCounter <= 0) {
-    showTiles();
-    logEvent(LOG_TYPE.NTP_ALL_TILES_LOADED);
-    window.parent.postMessage({cmd: 'loaded'}, DOMAIN_ORIGIN);
-    loadedCounter = 1;
+  'use strict';
+
+
+  /**
+   * The different types of events that are logged from the NTP.  This enum is
+   * used to transfer information from the NTP JavaScript to the renderer and is
+   * not used as a UMA enum histogram's logged value.
+   * Note: Keep in sync with common/ntp_logging_events.h
+   * @enum {number}
+   * @const
+   */
+  var LOG_TYPE = {
+    // All NTP Tiles have finished loading (successfully or failing).
+    NTP_ALL_TILES_LOADED: 11,
+  };
+
+
+  /**
+   * The different sources that an NTP tile can have.
+   * Note: Keep in sync with components/ntp_tiles/ntp_tile_source.h
+   * @enum {number}
+   * @const
+   */
+  var NTPTileSource = {
+    TOP_SITES: 0,
+    SUGGESTIONS_SERVICE: 1,
+    POPULAR: 3,
+    WHITELIST: 4,
+  };
+
+
+  /**
+   * Total number of tiles to show at any time. If the host page doesn't send
+   * enough tiles, we fill them blank.
+   * @const {number}
+   */
+  var NUMBER_OF_TILES = 8;
+
+
+  /**
+   * Whether to use icons instead of thumbnails.
+   * @type {boolean}
+   */
+  var USE_ICONS = false;
+
+
+  /**
+   * Number of lines to display in titles.
+   * @type {number}
+   */
+  var NUM_TITLE_LINES = 1;
+
+
+  /**
+   * The origin of this request.
+   * @const {string}
+   */
+  var DOMAIN_ORIGIN = '{{ORIGIN}}';
+
+
+  /**
+   * Counter for DOM elements that we are waiting to finish loading.
+   * @type {number}
+   */
+  var loadedCounter = 1;
+
+
+  /**
+   * DOM element containing the tiles we are going to present next.
+   * Works as a double-buffer that is shown when we receive a "show"
+   * postMessage.
+   * @type {Element}
+   */
+  var tiles = null;
+
+
+  /**
+   * List of parameters passed by query args.
+   * @type {Object}
+   */
+  var queryArgs = {};
+
+
+  /**
+   * Log an event on the NTP.
+   * @param {number} eventType Event from LOG_TYPE.
+   */
+  var logEvent = function(eventType) {
+    chrome.embeddedSearch.newTabPage.logEvent(eventType);
+  };
+
+  /**
+   * Log impression of an NTP tile.
+   * @param {number} tileIndex Position of the tile, >= 0 and < NUMBER_OF_TILES.
+   * @param {number} tileSource The source from NTPTileSource.
+   */
+  function logMostVisitedImpression(tileIndex, tileSource) {
+    chrome.embeddedSearch.newTabPage.logMostVisitedImpression(
+        tileIndex, tileSource);
   }
-};
 
+  /**
+   * Log click on an NTP tile.
+   * @param {number} tileIndex Position of the tile, >= 0 and < NUMBER_OF_TILES.
+   * @param {number} tileSource The source from NTPTileSource.
+   */
+  function logMostVisitedNavigation(tileIndex, tileSource) {
+    chrome.embeddedSearch.newTabPage.logMostVisitedNavigation(
+        tileIndex, tileSource);
+  }
 
-/**
- * Handles postMessages coming from the host page to the iframe.
- * Mostly, it dispatches every command to handleCommand.
- */
-var handlePostMessage = function(event) {
-  if (event.data instanceof Array) {
-    for (var i = 0; i < event.data.length; ++i) {
-      handleCommand(event.data[i]);
+  /**
+   * Down counts the DOM elements that we are waiting for the page to load.
+   * When we get to 0, we send a message to the parent window.
+   * This is usually used as an EventListener of onload/onerror.
+   */
+  var countLoad = function() {
+    loadedCounter -= 1;
+    if (loadedCounter <= 0) {
+      showTiles();
+      logEvent(LOG_TYPE.NTP_ALL_TILES_LOADED);
+      window.parent.postMessage({cmd: 'loaded'}, DOMAIN_ORIGIN);
+      loadedCounter = 1;
     }
-  } else {
-    handleCommand(event.data);
-  }
-};
-
-
-/**
- * Handles a single command coming from the host page to the iframe.
- * We try to keep the logic here to a minimum and just dispatch to the relevant
- * functions.
- */
-var handleCommand = function(data) {
-  var cmd = data.cmd;
-
-  if (cmd == 'tile') {
-    addTile(data);
-  } else if (cmd == 'show') {
-    countLoad();
-    hideOverflowTiles(data);
-  } else if (cmd == 'updateTheme') {
-    updateTheme(data);
-  } else if (cmd == 'tilesVisible') {
-    hideOverflowTiles(data);
-  } else {
-    console.error('Unknown command: ' + JSON.stringify(data));
-  }
-};
+  };
 
 
-var updateTheme = function(info) {
-  var themeStyle = [];
+  /**
+   * Handles postMessages coming from the host page to the iframe.
+   * Mostly, it dispatches every command to handleCommand.
+   */
+  var handlePostMessage = function(event) {
+    if (event.data instanceof Array) {
+      for (var i = 0; i < event.data.length; ++i) {
+        handleCommand(event.data[i]);
+      }
+    } else {
+      handleCommand(event.data);
+    }
+  };
 
-  if (info.tileBorderColor) {
-    themeStyle.push('.thumb-ntp .mv-tile {' +
-        'border: 1px solid ' + info.tileBorderColor + '; }');
-  }
-  if (info.tileHoverBorderColor) {
-    themeStyle.push('.thumb-ntp .mv-tile:hover {' +
-        'border-color: ' + info.tileHoverBorderColor + '; }');
-  }
-  if (info.isThemeDark) {
-    themeStyle.push('.thumb-ntp .mv-tile, .thumb-ntp .mv-empty-tile { ' +
-        'background: rgb(51,51,51); }');
-    themeStyle.push('.thumb-ntp .mv-thumb.failed-img { ' +
-        'background-color: #555; }');
-    themeStyle.push('.thumb-ntp .mv-thumb.failed-img::after { ' +
-        'border-color: #333; }');
-    themeStyle.push('.thumb-ntp .mv-x { ' +
-        'background: linear-gradient(to left, ' +
-        'rgb(51,51,51) 60%, transparent); }');
-    themeStyle.push('html[dir=rtl] .thumb-ntp .mv-x { ' +
-        'background: linear-gradient(to right, ' +
-        'rgb(51,51,51) 60%, transparent); }');
-    themeStyle.push('.thumb-ntp .mv-x::after { ' +
-        'background-color: rgba(255,255,255,0.7); }');
-    themeStyle.push('.thumb-ntp .mv-x:hover::after { ' +
-        'background-color: #fff; }');
-    themeStyle.push('.thumb-ntp .mv-x:active::after { ' +
-        'background-color: rgba(255,255,255,0.5); }');
-    themeStyle.push('.icon-ntp .mv-tile:focus { ' +
-        'background: rgba(255,255,255,0.2); }');
-  }
-  if (info.tileTitleColor) {
-    themeStyle.push('body { color: ' + info.tileTitleColor + '; }');
-  }
 
-  document.querySelector('#custom-theme').textContent = themeStyle.join('\n');
-};
+  /**
+   * Handles a single command coming from the host page to the iframe.
+   * We try to keep the logic here to a minimum and just dispatch to the
+   * relevant
+   * functions.
+   */
+  var handleCommand = function(data) {
+    var cmd = data.cmd;
 
+    if (cmd == 'tile') {
+      addTile(data);
+    } else if (cmd == 'show') {
+      countLoad();
+      hideOverflowTiles(data);
+    } else if (cmd == 'updateTheme') {
+      updateTheme(data);
+    } else if (cmd == 'tilesVisible') {
+      hideOverflowTiles(data);
+    } else {
+      console.error('Unknown command: ' + JSON.stringify(data));
+    }
+  };
 
-/**
- * Hides extra tiles that don't fit on screen.
- */
-var hideOverflowTiles = function(data) {
-  var tileAndEmptyTileList = document.querySelectorAll(
-      '#mv-tiles .mv-tile,#mv-tiles .mv-empty-tile');
-  for (var i = 0; i < tileAndEmptyTileList.length; ++i) {
-    tileAndEmptyTileList[i].classList.toggle('hidden', i >= data.maxVisible);
-  }
-};
 
+  var updateTheme = function(info) {
+    var themeStyle = [];
 
-/**
- * Removes all old instances of #mv-tiles that are pending for deletion.
- */
-var removeAllOldTiles = function() {
-  var parent = document.querySelector('#most-visited');
-  var oldList = parent.querySelectorAll('.mv-tiles-old');
-  for (var i = 0; i < oldList.length; ++i) {
-    parent.removeChild(oldList[i]);
-  }
-};
+    if (info.tileBorderColor) {
+      themeStyle.push(
+          '.thumb-ntp .mv-tile {' +
+          'border: 1px solid ' + info.tileBorderColor + '; }');
+    }
+    if (info.tileHoverBorderColor) {
+      themeStyle.push(
+          '.thumb-ntp .mv-tile:hover {' +
+          'border-color: ' + info.tileHoverBorderColor + '; }');
+    }
+    if (info.isThemeDark) {
+      themeStyle.push(
+          '.thumb-ntp .mv-tile, .thumb-ntp .mv-empty-tile { ' +
+          'background: rgb(51,51,51); }');
+      themeStyle.push(
+          '.thumb-ntp .mv-thumb.failed-img { ' +
+          'background-color: #555; }');
+      themeStyle.push(
+          '.thumb-ntp .mv-thumb.failed-img::after { ' +
+          'border-color: #333; }');
+      themeStyle.push(
+          '.thumb-ntp .mv-x { ' +
+          'background: linear-gradient(to left, ' +
+          'rgb(51,51,51) 60%, transparent); }');
+      themeStyle.push(
+          'html[dir=rtl] .thumb-ntp .mv-x { ' +
+          'background: linear-gradient(to right, ' +
+          'rgb(51,51,51) 60%, transparent); }');
+      themeStyle.push(
+          '.thumb-ntp .mv-x::after { ' +
+          'background-color: rgba(255,255,255,0.7); }');
+      themeStyle.push(
+          '.thumb-ntp .mv-x:hover::after { ' +
+          'background-color: #fff; }');
+      themeStyle.push(
+          '.thumb-ntp .mv-x:active::after { ' +
+          'background-color: rgba(255,255,255,0.5); }');
+      themeStyle.push(
+          '.icon-ntp .mv-tile:focus { ' +
+          'background: rgba(255,255,255,0.2); }');
+    }
+    if (info.tileTitleColor) {
+      themeStyle.push('body { color: ' + info.tileTitleColor + '; }');
+    }
 
+    document.querySelector('#custom-theme').textContent = themeStyle.join('\n');
+  };
 
-/**
- * Called when the host page has finished sending us tile information and
- * we are ready to show the new tiles and drop the old ones.
- */
-var showTiles = function() {
-  // Store the tiles on the current closure.
-  var cur = tiles;
 
-  // Create empty tiles until we have NUMBER_OF_TILES.
-  while (cur.childNodes.length < NUMBER_OF_TILES) {
-    addTile({});
-  }
+  /**
+   * Hides extra tiles that don't fit on screen.
+   */
+  var hideOverflowTiles = function(data) {
+    var tileAndEmptyTileList = document.querySelectorAll(
+        '#mv-tiles .mv-tile,#mv-tiles .mv-empty-tile');
+    for (var i = 0; i < tileAndEmptyTileList.length; ++i) {
+      tileAndEmptyTileList[i].classList.toggle('hidden', i >= data.maxVisible);
+    }
+  };
 
-  var parent = document.querySelector('#most-visited');
-
-  // Only fade in the new tiles if there were tiles before.
-  var fadeIn = false;
-  var old = parent.querySelector('#mv-tiles');
-  if (old) {
-    fadeIn = true;
-    // Mark old tile DIV for removal after the transition animation is done.
-    old.removeAttribute('id');
-    old.classList.add('mv-tiles-old');
-    old.style.opacity = 0.0;
-    cur.addEventListener('webkitTransitionEnd', function(ev) {
-      if (ev.target === cur) {
-        removeAllOldTiles();
-      }
-    });
-  }
 
-  // Add new tileset.
-  cur.id = 'mv-tiles';
-  parent.appendChild(cur);
-  // getComputedStyle causes the initial style (opacity 0) to be applied, so
-  // that when we then set it to 1, that triggers the CSS transition.
-  if (fadeIn) {
-    window.getComputedStyle(cur).opacity;
-  }
-  cur.style.opacity = 1.0;
-
-  // Make sure the tiles variable contain the next tileset we may use.
-  tiles = document.createElement('div');
-};
-
-
-/**
- * Called when the host page wants to add a suggestion tile.
- * For Most Visited, it grabs the data from Chrome and pass on.
- * For host page generated it just passes the data.
- * @param {object} args Data for the tile to be rendered.
- */
-var addTile = function(args) {
-  if (isFinite(args.rid)) {
-    // If a valid number passed in |args.rid|: a local chrome suggestion.
-    var data =
-        chrome.embeddedSearch.newTabPage.getMostVisitedItemData(args.rid);
-    if (!data)
-      return;
-
-    data.tid = data.rid;
-    if (!data.faviconUrl) {
-      data.faviconUrl = 'chrome-search://favicon/size/16@' +
-          window.devicePixelRatio + 'x/' + data.renderViewId + '/' + data.tid;
+  /**
+   * Removes all old instances of #mv-tiles that are pending for deletion.
+   */
+  var removeAllOldTiles = function() {
+    var parent = document.querySelector('#most-visited');
+    var oldList = parent.querySelectorAll('.mv-tiles-old');
+    for (var i = 0; i < oldList.length; ++i) {
+      parent.removeChild(oldList[i]);
     }
-    tiles.appendChild(renderTile(data));
-  } else if (args.url) {
-    // If a URL is passed: a server-side suggestion.
-    args.tileSource = NTPTileSource.SUGGESTIONS_SERVICE;
-    // check sanity of the arguments
-    if (/^javascript:/i.test(args.url) ||
-        /^javascript:/i.test(args.thumbnailUrl))
-      return;
-    tiles.appendChild(renderTile(args));
-  } else {  // an empty tile
-    tiles.appendChild(renderTile(null));
-  }
-};
-
-/**
- * Called when the user decided to add a tile to the blacklist.
- * It sets of the animation for the blacklist and sends the blacklisted id
- * to the host page.
- * @param {Element} tile DOM node of the tile we want to remove.
- */
-var blacklistTile = function(tile) {
-  tile.classList.add('blacklisted');
-  tile.addEventListener('webkitTransitionEnd', function(ev) {
-    if (ev.propertyName != 'width') return;
-
-    window.parent.postMessage({cmd: 'tileBlacklisted',
-                               tid: Number(tile.getAttribute('data-tid'))},
-                              DOMAIN_ORIGIN);
-  });
-};
-
-
-/**
- * Returns whether the given URL has a known, safe scheme.
- * @param {string} url URL to check.
- */
-var isSchemeAllowed = function(url) {
-  return url.startsWith('http://') || url.startsWith('https://') ||
-         url.startsWith('ftp://') || url.startsWith('file://') ||
-         url.startsWith('chrome-extension://');
-};
-
-
-/**
- * Renders a MostVisited tile to the DOM.
- * @param {object} data Object containing rid, url, title, favicon, thumbnail.
- *     data is null if you want to construct an empty tile.
- */
-var renderTile = function(data) {
-  var tile = document.createElement('a');
-
-  if (data == null) {
-    tile.className = 'mv-empty-tile';
-    return tile;
-  }
+  };
 
-  // The tile will be appended to tiles.
-  var position = tiles.children.length;
-  logMostVisitedImpression(position, data.tileSource);
 
-  tile.className = 'mv-tile';
-  tile.setAttribute('data-tid', data.tid);
-  var html = [];
-  if (!USE_ICONS) {
-    html.push('<div class="mv-favicon"></div>');
-  }
-  html.push('<div class="mv-title"></div><div class="mv-thumb"></div>');
-  html.push('<div class="mv-x" role="button"></div>');
-  tile.innerHTML = html.join('');
-  tile.lastElementChild.title = queryArgs['removeTooltip'] || '';
+  /**
+   * Called when the host page has finished sending us tile information and
+   * we are ready to show the new tiles and drop the old ones.
+   */
+  var showTiles = function() {
+    // Store the tiles on the current closure.
+    var cur = tiles;
 
-  if (isSchemeAllowed(data.url)) {
-    tile.href = data.url;
-  }
-  tile.setAttribute('aria-label', data.title);
-  tile.title = data.title;
-
-  tile.addEventListener('click', function(ev) {
-    logMostVisitedNavigation(position, data.tileSource);
-  });
-
-  tile.addEventListener('keydown', function(event) {
-    if (event.keyCode == 46 /* DELETE */ ||
-        event.keyCode == 8 /* BACKSPACE */) {
-      event.preventDefault();
-      event.stopPropagation();
-      blacklistTile(this);
-    } else if (event.keyCode == 13 /* ENTER */ ||
-               event.keyCode == 32 /* SPACE */) {
-      event.preventDefault();
-      this.click();
-    } else if (event.keyCode >= 37 && event.keyCode <= 40 /* ARROWS */) {
-      // specify the direction of movement
-      var inArrowDirection = function(origin, target) {
-        return (event.keyCode == 37 /* LEFT */ &&
-                origin.offsetTop == target.offsetTop &&
-                origin.offsetLeft > target.offsetLeft) ||
-                (event.keyCode == 38 /* UP */ &&
-                origin.offsetTop > target.offsetTop &&
-                origin.offsetLeft == target.offsetLeft) ||
-                (event.keyCode == 39 /* RIGHT */ &&
-                origin.offsetTop == target.offsetTop &&
-                origin.offsetLeft < target.offsetLeft) ||
-                (event.keyCode == 40 /* DOWN */ &&
-                origin.offsetTop < target.offsetTop &&
-                origin.offsetLeft == target.offsetLeft);
-      };
+    // Create empty tiles until we have NUMBER_OF_TILES.
+    while (cur.childNodes.length < NUMBER_OF_TILES) {
+      addTile({});
+    }
 
-      var nonEmptyTiles = document.querySelectorAll('#mv-tiles .mv-tile');
-      var nextTile = null;
-      // Find the closest tile in the appropriate direction.
-      for (var i = 0; i < nonEmptyTiles.length; i++) {
-        if (inArrowDirection(this, nonEmptyTiles[i]) &&
-            (!nextTile || inArrowDirection(nonEmptyTiles[i], nextTile))) {
-          nextTile = nonEmptyTiles[i];
+    var parent = document.querySelector('#most-visited');
+
+    // Only fade in the new tiles if there were tiles before.
+    var fadeIn = false;
+    var old = parent.querySelector('#mv-tiles');
+    if (old) {
+      fadeIn = true;
+      // Mark old tile DIV for removal after the transition animation is done.
+      old.removeAttribute('id');
+      old.classList.add('mv-tiles-old');
+      old.style.opacity = 0.0;
+      cur.addEventListener('webkitTransitionEnd', function(ev) {
+        if (ev.target === cur) {
+          removeAllOldTiles();
         }
+      });
+    }
+
+    // Add new tileset.
+    cur.id = 'mv-tiles';
+    parent.appendChild(cur);
+    // getComputedStyle causes the initial style (opacity 0) to be applied, so
+    // that when we then set it to 1, that triggers the CSS transition.
+    if (fadeIn) {
+      window.getComputedStyle(cur).opacity;
+    }
+    cur.style.opacity = 1.0;
+
+    // Make sure the tiles variable contain the next tileset we may use.
+    tiles = document.createElement('div');
+  };
+
+
+  /**
+   * Called when the host page wants to add a suggestion tile.
+   * For Most Visited, it grabs the data from Chrome and pass on.
+   * For host page generated it just passes the data.
+   * @param {object} args Data for the tile to be rendered.
+   */
+  var addTile = function(args) {
+    if (isFinite(args.rid)) {
+      // If a valid number passed in |args.rid|: a local chrome suggestion.
+      var data =
+          chrome.embeddedSearch.newTabPage.getMostVisitedItemData(args.rid);
+      if (!data)
+        return;
+
+      data.tid = data.rid;
+      if (!data.faviconUrl) {
+        data.faviconUrl = 'chrome-search://favicon/size/16@' +
+            window.devicePixelRatio + 'x/' + data.renderViewId + '/' + data.tid;
       }
-      if (nextTile) {
-        nextTile.focus();
-      }
+      tiles.appendChild(renderTile(data));
+    } else if (args.url) {
+      // If a URL is passed: a server-side suggestion.
+      args.tileSource = NTPTileSource.SUGGESTIONS_SERVICE;
+      // check sanity of the arguments
+      if (/^javascript:/i.test(args.url) ||
+          /^javascript:/i.test(args.thumbnailUrl))
+        return;
+      tiles.appendChild(renderTile(args));
+    } else {  // an empty tile
+      tiles.appendChild(renderTile(null));
     }
-  });
+  };
+
+  /**
+   * Called when the user decided to add a tile to the blacklist.
+   * It sets of the animation for the blacklist and sends the blacklisted id
+   * to the host page.
+   * @param {Element} tile DOM node of the tile we want to remove.
+   */
+  var blacklistTile = function(tile) {
+    tile.classList.add('blacklisted');
+    tile.addEventListener('webkitTransitionEnd', function(ev) {
+      if (ev.propertyName != 'width')
+        return;
 
-  var title = tile.querySelector('.mv-title');
-  title.innerText = data.title;
-  title.style.direction = data.direction || 'ltr';
-  if (NUM_TITLE_LINES > 1) {
-    title.classList.add('multiline');
-  }
+      window.parent.postMessage(
+          {cmd: 'tileBlacklisted', tid: Number(tile.getAttribute('data-tid'))},
+          DOMAIN_ORIGIN);
+    });
+  };
+
+
+  /**
+   * Returns whether the given URL has a known, safe scheme.
+   * @param {string} url URL to check.
+   */
+  var isSchemeAllowed = function(url) {
+    return url.startsWith('http://') || url.startsWith('https://') ||
+        url.startsWith('ftp://') || url.startsWith('file://') ||
+        url.startsWith('chrome-extension://');
+  };
+
+
+  /**
+   * Renders a MostVisited tile to the DOM.
+   * @param {object} data Object containing rid, url, title, favicon, thumbnail.
+   *     data is null if you want to construct an empty tile.
+   */
+  var renderTile = function(data) {
+    var tile = document.createElement('a');
+
+    if (data == null) {
+      tile.className = 'mv-empty-tile';
+      return tile;
+    }
+
+    // The tile will be appended to tiles.
+    var position = tiles.children.length;
+    logMostVisitedImpression(position, data.tileSource);
+
+    tile.className = 'mv-tile';
+    tile.setAttribute('data-tid', data.tid);
+    var html = [];
+    if (!USE_ICONS) {
+      html.push('<div class="mv-favicon"></div>');
+    }
+    html.push('<div class="mv-title"></div><div class="mv-thumb"></div>');
+    html.push('<div class="mv-x" role="button"></div>');
+    tile.innerHTML = html.join('');
+    tile.lastElementChild.title = queryArgs['removeTooltip'] || '';
+
+    if (isSchemeAllowed(data.url)) {
+      tile.href = data.url;
+    }
+    tile.setAttribute('aria-label', data.title);
+    tile.title = data.title;
+
+    tile.addEventListener('click', function(ev) {
+      logMostVisitedNavigation(position, data.tileSource);
+    });
 
-  if (USE_ICONS) {
-    var thumb = tile.querySelector('.mv-thumb');
-    if (data.largeIconUrl) {
+    tile.addEventListener('keydown', function(event) {
+      if (event.keyCode == 46 /* DELETE */ ||
+          event.keyCode == 8 /* BACKSPACE */) {
+        event.preventDefault();
+        event.stopPropagation();
+        blacklistTile(this);
+      } else if (
+          event.keyCode == 13 /* ENTER */ || event.keyCode == 32 /* SPACE */) {
+        event.preventDefault();
+        this.click();
+      } else if (event.keyCode >= 37 && event.keyCode <= 40 /* ARROWS */) {
+        // specify the direction of movement
+        var inArrowDirection = function(origin, target) {
+          return (event.keyCode == 37 /* LEFT */ &&
+                  origin.offsetTop == target.offsetTop &&
+                  origin.offsetLeft > target.offsetLeft) ||
+              (event.keyCode == 38 /* UP */ &&
+               origin.offsetTop > target.offsetTop &&
+               origin.offsetLeft == target.offsetLeft) ||
+              (event.keyCode == 39 /* RIGHT */ &&
+               origin.offsetTop == target.offsetTop &&
+               origin.offsetLeft < target.offsetLeft) ||
+              (event.keyCode == 40 /* DOWN */ &&
+               origin.offsetTop < target.offsetTop &&
+               origin.offsetLeft == target.offsetLeft);
+        };
+
+        var nonEmptyTiles = document.querySelectorAll('#mv-tiles .mv-tile');
+        var nextTile = null;
+        // Find the closest tile in the appropriate direction.
+        for (var i = 0; i < nonEmptyTiles.length; i++) {
+          if (inArrowDirection(this, nonEmptyTiles[i]) &&
+              (!nextTile || inArrowDirection(nonEmptyTiles[i], nextTile))) {
+            nextTile = nonEmptyTiles[i];
+          }
+        }
+        if (nextTile) {
+          nextTile.focus();
+        }
+      }
+    });
+
+    var title = tile.querySelector('.mv-title');
+    title.innerText = data.title;
+    title.style.direction = data.direction || 'ltr';
+    if (NUM_TITLE_LINES > 1) {
+      title.classList.add('multiline');
+    }
+
+    if (USE_ICONS) {
+      var thumb = tile.querySelector('.mv-thumb');
+      if (data.largeIconUrl) {
+        var img = document.createElement('img');
+        img.title = data.title;
+        img.src = data.largeIconUrl;
+        img.classList.add('large-icon');
+        loadedCounter += 1;
+        img.addEventListener('load', countLoad);
+        img.addEventListener('load', function(ev) {
+          thumb.classList.add('large-icon-outer');
+        });
+        img.addEventListener('error', countLoad);
+        img.addEventListener('error', function(ev) {
+          thumb.classList.add('failed-img');
+          thumb.removeChild(img);
+        });
+        thumb.appendChild(img);
+      } else {
+        thumb.classList.add('failed-img');
+      }
+    } else {  // THUMBNAILS
+      // We keep track of the outcome of loading possible thumbnails for this
+      // tile. Possible values:
+      //   - null: waiting for load/error
+      //   - false: error
+      //   - a string: URL that loaded correctly.
+      // This is populated by acceptImage/rejectImage and loadBestImage
+      // decides the best one to load.
+      var results = [];
+      var thumb = tile.querySelector('.mv-thumb');
       var img = document.createElement('img');
+      var loaded = false;
+
+      var loadBestImage = function() {
+        if (loaded) {
+          return;
+        }
+        for (var i = 0; i < results.length; ++i) {
+          if (results[i] === null) {
+            return;
+          }
+          if (results[i] != false) {
+            img.src = results[i];
+            loaded = true;
+            return;
+          }
+        }
+        thumb.classList.add('failed-img');
+        thumb.removeChild(img);
+        countLoad();
+      };
+
+      var acceptImage = function(idx, url) {
+        return function(ev) {
+          results[idx] = url;
+          loadBestImage();
+        };
+      };
+
+      var rejectImage = function(idx) {
+        return function(ev) {
+          results[idx] = false;
+          loadBestImage();
+        };
+      };
+
       img.title = data.title;
-      img.src = data.largeIconUrl;
-      img.classList.add('large-icon');
+      img.classList.add('thumbnail');
       loadedCounter += 1;
       img.addEventListener('load', countLoad);
-      img.addEventListener('load', function(ev) {
-        thumb.classList.add('large-icon-outer');
-      });
       img.addEventListener('error', countLoad);
       img.addEventListener('error', function(ev) {
         thumb.classList.add('failed-img');
         thumb.removeChild(img);
       });
       thumb.appendChild(img);
-    } else {
-      thumb.classList.add('failed-img');
-    }
-  } else { // THUMBNAILS
-    // We keep track of the outcome of loading possible thumbnails for this
-    // tile. Possible values:
-    //   - null: waiting for load/error
-    //   - false: error
-    //   - a string: URL that loaded correctly.
-    // This is populated by acceptImage/rejectImage and loadBestImage
-    // decides the best one to load.
-    var results = [];
-    var thumb = tile.querySelector('.mv-thumb');
-    var img = document.createElement('img');
-    var loaded = false;
-
-    var loadBestImage = function() {
-      if (loaded) {
-        return;
-      }
-      for (var i = 0; i < results.length; ++i) {
-        if (results[i] === null) {
-          return;
+
+      if (data.thumbnailUrl) {
+        img.src = data.thumbnailUrl;
+      } else {
+        // Get all thumbnailUrls for the tile.
+        // They are ordered from best one to be used to worst.
+        for (var i = 0; i < data.thumbnailUrls.length; ++i) {
+          results.push(null);
         }
-        if (results[i] != false) {
-          img.src = results[i];
-          loaded = true;
-          return;
+        for (var i = 0; i < data.thumbnailUrls.length; ++i) {
+          if (data.thumbnailUrls[i]) {
+            var image = new Image();
+            image.src = data.thumbnailUrls[i];
+            image.onload = acceptImage(i, data.thumbnailUrls[i]);
+            image.onerror = rejectImage(i);
+          } else {
+            rejectImage(i)(null);
+          }
         }
       }
-      thumb.classList.add('failed-img');
-      thumb.removeChild(img);
-      countLoad();
-    };
 
-    var acceptImage = function(idx, url) {
-      return function(ev) {
-        results[idx] = url;
-        loadBestImage();
-      };
-    };
+      var favicon = tile.querySelector('.mv-favicon');
+      if (data.faviconUrl) {
+        var fi = document.createElement('img');
+        fi.src = data.faviconUrl;
+        // Set the title to empty so screen readers won't say the image name.
+        fi.title = '';
+        loadedCounter += 1;
+        fi.addEventListener('load', countLoad);
+        fi.addEventListener('error', countLoad);
+        fi.addEventListener('error', function(ev) {
+          favicon.classList.add('failed-favicon');
+        });
+        favicon.appendChild(fi);
+      } else {
+        favicon.classList.add('failed-favicon');
+      }
+    }
 
-    var rejectImage = function(idx) {
-      return function(ev) {
-        results[idx] = false;
-        loadBestImage();
-      };
-    };
-
-    img.title = data.title;
-    img.classList.add('thumbnail');
-    loadedCounter += 1;
-    img.addEventListener('load', countLoad);
-    img.addEventListener('error', countLoad);
-    img.addEventListener('error', function(ev) {
-      thumb.classList.add('failed-img');
-      thumb.removeChild(img);
+    var mvx = tile.querySelector('.mv-x');
+    mvx.addEventListener('click', function(ev) {
+      removeAllOldTiles();
+      blacklistTile(tile);
+      ev.preventDefault();
+      ev.stopPropagation();
     });
-    thumb.appendChild(img);
 
-    if (data.thumbnailUrl) {
-      img.src = data.thumbnailUrl;
-    } else {
-      // Get all thumbnailUrls for the tile.
-      // They are ordered from best one to be used to worst.
-      for (var i = 0; i < data.thumbnailUrls.length; ++i) {
-        results.push(null);
-      }
-      for (var i = 0; i < data.thumbnailUrls.length; ++i) {
-        if (data.thumbnailUrls[i]) {
-          var image = new Image();
-          image.src = data.thumbnailUrls[i];
-          image.onload = acceptImage(i, data.thumbnailUrls[i]);
-          image.onerror = rejectImage(i);
-        } else {
-          rejectImage(i)(null);
-        }
-      }
+    return tile;
+  };
+
+
+  /**
+   * Do some initialization and parses the query arguments passed to the iframe.
+   */
+  var init = function() {
+    // Creates a new DOM element to hold the tiles.
+    tiles = document.createElement('div');
+
+    // Parse query arguments.
+    var query = window.location.search.substring(1).split('&');
+    queryArgs = {};
+    for (var i = 0; i < query.length; ++i) {
+      var val = query[i].split('=');
+      if (val[0] == '')
+        continue;
+      queryArgs[decodeURIComponent(val[0])] = decodeURIComponent(val[1]);
     }
 
-    var favicon = tile.querySelector('.mv-favicon');
-    if (data.faviconUrl) {
-      var fi = document.createElement('img');
-      fi.src = data.faviconUrl;
-      // Set the title to empty so screen readers won't say the image name.
-      fi.title = '';
-      loadedCounter += 1;
-      fi.addEventListener('load', countLoad);
-      fi.addEventListener('error', countLoad);
-      fi.addEventListener('error', function(ev) {
-        favicon.classList.add('failed-favicon');
-      });
-      favicon.appendChild(fi);
-    } else {
-      favicon.classList.add('failed-favicon');
+    // Apply class for icon NTP, if specified.
+    USE_ICONS = queryArgs['icons'] == '1';
+    if ('ntl' in queryArgs) {
+      var ntl = parseInt(queryArgs['ntl'], 10);
+      if (isFinite(ntl))
+        NUM_TITLE_LINES = ntl;
     }
-  }
 
-  var mvx = tile.querySelector('.mv-x');
-  mvx.addEventListener('click', function(ev) {
-    removeAllOldTiles();
-    blacklistTile(tile);
-    ev.preventDefault();
-    ev.stopPropagation();
-  });
-
-  return tile;
-};
-
-
-/**
- * Do some initialization and parses the query arguments passed to the iframe.
- */
-var init = function() {
-  // Creates a new DOM element to hold the tiles.
-  tiles = document.createElement('div');
-
-  // Parse query arguments.
-  var query = window.location.search.substring(1).split('&');
-  queryArgs = {};
-  for (var i = 0; i < query.length; ++i) {
-    var val = query[i].split('=');
-    if (val[0] == '') continue;
-    queryArgs[decodeURIComponent(val[0])] = decodeURIComponent(val[1]);
-  }
-
-  // Apply class for icon NTP, if specified.
-  USE_ICONS = queryArgs['icons'] == '1';
-  if ('ntl' in queryArgs) {
-    var ntl = parseInt(queryArgs['ntl'], 10);
-    if (isFinite(ntl))
-      NUM_TITLE_LINES = ntl;
-  }
+    // Duplicating NTP_DESIGN.mainClass.
+    document.querySelector('#most-visited')
+        .classList.add(USE_ICONS ? 'icon-ntp' : 'thumb-ntp');
 
-  // Duplicating NTP_DESIGN.mainClass.
-  document.querySelector('#most-visited').classList.add(
-      USE_ICONS ? 'icon-ntp' : 'thumb-ntp');
-
-  // Enable RTL.
-  if (queryArgs['rtl'] == '1') {
-    var html = document.querySelector('html');
-    html.dir = 'rtl';
-  }
+    // Enable RTL.
+    if (queryArgs['rtl'] == '1') {
+      var html = document.querySelector('html');
+      html.dir = 'rtl';
+    }
 
-  window.addEventListener('message', handlePostMessage);
-};
+    window.addEventListener('message', handlePostMessage);
+  };
 
 
-window.addEventListener('DOMContentLoaded', init);
+  window.addEventListener('DOMContentLoaded', init);
 })();